-----------------------------------------------------------------------------
LEDA-7.2.2 
-----------------------------------------------------------------------------

Adjustments for g++ 15.2

Problem with unused return value in src/system/_file.cpp fixed


-----------------------------------------------------------------------------
LEDA-7.1 
-----------------------------------------------------------------------------

Bug in dlist (doubly linked list base class)

  error in move constructor fixed (incorrect tail-pointer) 
  This bug could cause memory leaks in some situations.



-----------------------------------------------------------------------------
LEDA-6.6.1 
------------------------------------------------------------------------------

Bug in param_types.h fixed

   leda_cast made an unecessary copy if size(T) = sizeof(GenPtr)
   causing memory leaks e.g. when using handle types




-----------------------------------------------------------------------------
LEDA-6.6 
------------------------------------------------------------------------------

changes for support of g++ versions 5.x.x, 6.x.x, 7.x.x, 8.x.x, 9.x.x

64-bit Windows
	 -- return value default compare fixed
	 -- return value ID_Number fixed

multithreading
         -- fix in spinlock

graph
         -- fix in default compare for edges/nodes
		 -- fix in node_partition

graph algorithms
         -- overflow problem fixed in MAX_WEIGHTED_MATCHING

partitions and node_partitions
         -- fix for a problem in the make_rep method

rational geometry
         -- fix in contructor of rat_gen_polygon
		 -- fix in unite function of gen_polygon and rat_gen_polygon 

circular geometry
         -- fix in buffer function of r_circle_gen_polygon

warnings
         -- number of changes in different files in order to prevent non-critical
		 -- warnings that arose when compiling with -Wall (Linux) or -W4 (Microsoft)

Manual
         -- typos and minor errors fixed
		 -- Chapter Implementations updated
         -- Chapter Technical Information updated



-----------------------------------------------------------------------------
LEDA-6.5 
------------------------------------------------------------------------------

changes for current g++ version (5.4)
         -- warnings about unused variables eliminated

multi threading
         -- type of thread_id changed from unsigned to unsigned long

max_flow
         -- checking enabled
         -- mincut heuristice removed

param_types
         -- 64 bit specialization fixed
		
real kernel
         -- area computation of polygon made more robust
		
circular geometry
         -- fix in approximate_area in r_circle_polygon
         -- fix in orientation of r_circle_gen_polygon
         -- fix in construct_arc for buffering
		
graph algorithmis
         -- fix in K_SHORTEST_PATHS in shortest_path
		
standard memory manager
         -- allocate_list fixed
		
multithread memory manager
         -- table of managers in add_manager fixed

		

-----------------------------------------------------------------------------
LEDA-6.4
------------------------------------------------------------------------------

real numbers
         -- bug in "sign_with_separation_bound"


CHECK_KURATOWSKI
         -- added missing return statement


Manual
         -- typos and minor errors fixed


gen_polygon
         -- bug in "extend_labeling"  (communicated by zhang yun 11/3/9)


Write/Read_Dimacs_MF/MCF/SP/..
         -- added missing versions for double cap/cost values


static graph implementation
         -- 64 bit support for Microsoft, 
           "unsigned long" replaced by proper type
                 
graph_register
         -- multithread problem fixed for Microsoft 64 bit
                 

mapping with chaining
         -- 64 bit support for Microsoft, 
            "unsigned long" replaced by proper type


r_circle_segment
         -- bug in member function middle fixed



-----------------------------------------------------------------------------
LEDA-6.3
------------------------------------------------------------------------------

min cost flow
         -- bug in cost scaling algorithm fixed

node/edge_array 
         -- problems with multi-thread programs fixed

mt_memory_manager
         -- memory leak under windows (LEDA_THREAD_BEGIN macro) 

d3_window
         -- event handling problem fixed

-----------------------------------------------------------------------------
LEDA-6.2.2
------------------------------------------------------------------------------

xlman
         -- ascii demos now work as expected

graphics
         -- buffer overflow in x_load_font fixed
         -- draw_filled_polygon:
            problem with non-weakly polygons fixed
graphwin
         -- problem with connecting to AGD server fixed
         -- problem in AGD server dialog fixed

geometry
         -- fixed bug in buffer computation (r_circle_polygon)

MAX_WEIGHT_MATCHING: 
         -- special versions for undirected graphs (ugraph)
         -- exception in case of illegal heuristic parameter

MAX_CARD_MATCHING: 
         -- special versions for undirected graphs (ugraph)

MIN_COST_FLOW
         -- bug in mcf_cost_scaling fixed (inf_bound/af_factor too small)


-----------------------------------------------------------------------------
LEDA-6.2.1
------------------------------------------------------------------------------


GRAPH<T1,T2>:  problem with special variants of G.new_edge(...) fixed

param_types.h:  improved handling of gcc -O2 problem  (gcc-4.3)


MAXFLOW: - replaced capacity value-parameter by reference parameter
         - added missing scale_weights call in floating-point version

count_streambuf:  removed __exportC (solves DLL problem)

bigfloat input operator (>>):
    -replaced fixed size buffer by dynamic string 
    -input of negative values now works correctly


AGD:  changes for fixing compilation problems with latest gcc


-----------------------------------------------------------------------------
LEDA-6.2
------------------------------------------------------------------------------


parameterized partition: bug in make_block (number of blocks not counted)

integer/bigfloat:  mutexes were not properly destroyed in destructor

graphics(mswin):   increased number of colors (MAX_COLORS) to 2048

components/bicomponents:  fixed problem with undirected graphs (infinite loop)
                          fixed problem with self-loops

graph algorithms:
           dijkstra now works for undirected graphs
           min_cost_flow (cost scaling) 
               - now can deal with problems where all edges have cost zero
               - some infeasible problems have been handled incorrectly


-----------------------------------------------------------------------------
LEDA-6.1
------------------------------------------------------------------------------

point_set:  bug in point_set::compute_voronoi fixed
            (incorrect edge labels)

list:     problem in destructor for large element types
          (fixed by a new version of deallocate_list)

h_array:  nested forall_defined loops did not work


-----------------------------------------------------------------------------
LEDA-6.0
------------------------------------------------------------------------------


r_circle_polygon: bug in approximate_area() fixed 

r_circle_polygon: exception problem in constructor fixed

r_circle_polygon: test for weak simplicity always returned true

array2   : bug in constructor/destructor

graphics : scalable font problem under x11 fixed

integer  : problem with modulo-operator (%) fixed

bigfloat/real :  uninitialized mutex in bigfloat constructor

(gen_)polygon : transformations (translate, rotate90, reflect ...)
                could produce inconsistent representations 
    
graph :   CopyGraph did not work correctly for undirected graphs

          problem with conflicting definitions of forall-iteration macros for
          graph and static_graph no longer exists.



------------------------------------------------------------------------------
LEDA-5.2
------------------------------------------------------------------------------

point_set: bug in k-nearest-neighbor search fixed
           now result is ordered by distance from query point for k >= n

array:    bug in default-constructor fixed 

integer:  bug in double_quotient(a,b) fixed
          bug in new_rep (uninitialized mutex) fixed

MIN_COST_FLOW:
          cost scaling did not handle self-loops correctly (fixed)

d_int_set:
          bug on 64-bit platforms fixed

Makefiles:
          problem with gnu make solved (sometimes new object files were not 
          added to the corresponding library archive)

------------------------------------------------------------------------------
LEDA-5.1.1
------------------------------------------------------------------------------

g++ >= 4.0:  -O2 optimization problems solved (new version of param_types.h)

node_pq/bin_heap
   serious memory bug fixed (occured when using system mememory manager)

h_array:
   memory leak in operator= fixed.

graph_register.h:
   bug fixed

integer.h
   bug in modulo-operator (operator%) fixed 

------------------------------------------------------------------------------
LEDA-5.1
------------------------------------------------------------------------------

rat_point
  p.normalize() did not update floating point approximations 
  of the homogeneous coordinates (XD(),YD(),WD()), fixed.

  p.xcoordD() and p.ycoordD() now first normalize the coordinates
  before computing the floating point approximations to avoid
  overflow conditions (NaN values).
  
array
  fixed permute problem, first element was never permuted

min cost flow
  fixed mispelling in MIN_COST_FLOW with lcap=0

integer_vector
  fixed bug reported by M. Behle
  
d_int_set
  fixed bug in join when first set is empty
  
interval
  fixed bug for AMD64

segment_set/rat_segment_set
  fixed some bugs

rat_vector
  fixed bug in rotate90

r_circle_gen_polygon
  fixed bug in operator<<

real
  fixed bug in error computation of negation and sqrt; fixed
  bug in convert_to_dbl
  fixed separation bound for rational

eb_tree
  fixed implementation, was not usable anymore


FIVE_COLOR
  serious bug fixed 
   

------------------------------------------------------------------------------
LEDA-5.0.1
------------------------------------------------------------------------------

static_graph
  added missing destructor

cuckoo_hash
  fixed some bugs
  
segment_set
  fixed memory leak and bug in intersection query
  
real_point
  added work-around for compiler bug in Borland 5.6
  
real_point, rat_point, point
  fix for MSVC6 (related to mod arithmetics)
  
MW_MATCHING
  fixed some bugs
  
EULER_TOUR
  fixed bug

min cost flow
  removed bug in capacity scaling

graphwin
  added missing assignment operator for edge_info
  gw_move_edge_slider made safer
  
memory_manager
  LEDA_MEMORY macro: operator delete is now safe for NULL-pointers
  added work-around for compiler bug in Borland 5.6

Rijndael
  fixed bug in destructor

r_circle_segment sweep
  fixed bug related to isolated nodes
  
bigfloat
  fixed bug in sqrt_bf
  
interval
  fixed several bugs

fpu
  fixed false initial fpu rounding mode for Solaris

------------------------------------------------------------------------------
LEDA-5.0
------------------------------------------------------------------------------
r_heap
        bugfix on 64-bit platforms

cuckoo_hash
        bugfix on 64-bit platforms

FEASIBLE_FLOW
        bugfix (endless loop for some inputs)

graph
        write/read problems with DOS file format fixed

GraphWin
        writing and reading of graphs (gw-format) fixed
        connection to AGD-server now works again

window
        fixed bug in create_pixrect(string filename) (both Windows and Linux)
        transparent xpm are now displayed correctly

r_circle_point
        fixed bug in constructor r_circle_point(const rat_circle& c, const rat_line& l, tag which)

AutoDecoder
        fixed bug in constructor AutoDecoder(const char*, const char*)

------------------------------------------------------------------------------
LEDA-4.5
------------------------------------------------------------------------------

Manual
            fixed several misspellings, definitely improved description of many
            types and algorithms (several errors reported by J. Ziegler)

b_priority_queue
            manual entries were missing
            
bigfloat
            to_string() function added an unwanted char to the output -fixed

graph
                    write() function did not write whether graph was undirected or directed. As a
            result, the graph was always directed when it was read from a file; fixed.

GraphWin    
            destructor crash fixed (reported by T. Erlebach)
            additional features documented
            misplaced arrow in the drawings: fixed
                     
LEDA/misc.h
            fixed undef error for min and max

ALL_PAIR_SHORTEST_PATH
            Extra node that is added to perform the computation was not removed when the
            function returned false, fixed.

STRAIGHT_LINE_EMBEDDING
            did not work for graphs with only two nodes; fixed.

bin_heap
            fixed error in copy constructor (reported by. T. Willhalm)
            


------------------------------------------------------------------------------
LEDA-4.4.1
------------------------------------------------------------------------------

graphwin
           bug in destructor (reported by T. Erlebach) fixed

window
           bug in destructor fixed 
           X-error bad font problem when starting second graphwin 
           fixed (Linux/Unix platforms only)

real
          "sign cannot be determined"-bug fixed

graph
           node_array::use_node_data(G)
           edge_array::use_edge_data(G)
           did not work in 4.4 (slots were never used!), fixed. 
           bug in compare for nodes, edges, fixed

graph_iterators
           changes in <LEDA/graph_iterator.h> to make graph iterators 
           work with namespace leda
           bug in reinitialization of adjacent iterators, fixed

gml_graph
           not exported to DLL (missing __exportC)


graph_alg
           CHECK_MAX_FLOW  always reported error (fval != excess[t])
           INDEPENDENT_SET multiple removal of nodes 
           MIN_COST_FLOW access violation in rare cases, 
           fixed by new improved version (see Changes)

graph_map
           memory leak, fixed

node_map  
           bug in lazy extension of map fixed

pp_dictionary
           bug in compare fixed

convex hull
           pointer delete problem fixed

point
           bug in reflect fixed
           

geometry kernel on .NET and SPARC v9
           rounding mode was not set TO_NEAREST, fixed                        

number types 
           integer,bigfloat,real are now thread-safe

int_set/d_int_set
           workaround for MSC6-Bug (static const replaced by enum)

ab_tree
           functions min_item, max_item missing (necessary for
           usage as implementation parameter), fixed

gen_polygon
           bug in constructor, fixed
           
array / list
           print - minor problems fixed, functions now behave indentical
           
d3_plane / d3_rat_plane
           bug in intersection fixed

Manual
           many minor changes

------------------------------------------------------------------------------
LEDA-4.4
------------------------------------------------------------------------------

(rat_)triangle
       bug in region_of fixed

d_int_set::choose
       fixed as suggested by Thomas Erlebach

h_array::size
       was not declared as const

scale_weights:
       incorrect return value for identical input and output arrays
       (fix as suggested by D. Martindale on comp.lang.c++.leda)

INDEPENDENT_SET:
       multiple removal of nodes fixed

transform:
       bug in reflection at point fixed

GraphWin:
      moving of nodes was not correctly visualized for Undirected Graphs
      multiple display() calls crashed program (status window)
      set_frame_label() did not work if called before display()


------------------------------------------------------------------------------
LEDA-4.3.1
------------------------------------------------------------------------------


number package:
       fixed problems with sparc-v9 (64 bit) fpu assembler functions
       renamed problematic global names (e.g. "base", or "sz_t") in digit.h 
       fixed memory leak in rational operator+

point_set:
      bug fixed in compute_voronoi (only occured for "degenerate input") 

bin_heap:
      bug in bin_heap(int n) - Konstruktor (for n == 1)
      (caused a problem in _mcf_cap_scaling.c).
     
window:
     exporting a windows meta file did not work under windows 2000
     colors change after a number of zooming operations
     (problem with tmp font table in x11.c fixed)

     W.put_pixrect(prect) did not work correctly in presence of a menu bar


------------------------------------------------------------------------------
LEDA-4.3
------------------------------------------------------------------------------

general:

     gen_polygon and rat_gen_polygon added to REDEFINE_NAMES.h
     and UNDEFINE_NAMES.h

handle_types:
     mutex unlocks for already deleted objects 

array:
     operator= and copy constructor could not handle empty arrays
     A.resize(int sz) could not create an empty array (sz=0)

graph_alg:
     BFS(G,s,dist,pred): missing pred[s] = nil assignment

point_set:
     T.compute_voronoi(GRAPH<CIRCLE,POINT>& V)
     missing reversal pointers in V added

bool line::intersection(segment,point&)
     result was not correct for colinear segments


polygon/gen_polygon:
     changed Test in input operator to WEAKLY_SIMPLE
     (otherwise weakly-simple polygons cannot be read)

     check_weak_simplicity was not correct for (degenerated)
     polygons with less than 4 points


Is_Undirected_Simple (former Is_Simple_Undirected)
    did not work for graphs with more than 2^16 nodes


VISIBILITY_REPRESENTATION (graph_draw)
    failed in presence of more than two parallel edges



Window
   renamed W.draw_rectangle(p,q,rndness col)  to W.draw_roundrect(p,q, ...)

   file_panel could not handle initial file name of length 0 (empty string)



------------------------------------------------------------------------------
LEDA-4.2.1
------------------------------------------------------------------------------


point
      missing functions  inside/on/outside_circle  added

node_pq
      bug in print_node method

random_source
      added private copy_constructor

events
      problem with macros solved by using no-macro version

polygon
      bug in bounding_box method fixed
      bug in simplicity test fixed



------------------------------------------------------------------------------
LEDA-4.2
------------------------------------------------------------------------------



dynamic_trees
       bug in evert operation has been fixed

slist
       assignment (operator=) was not guarded against self-assignment

matrix
       in matrix::triang an array was deleted without "[]"
       

_d_array:
       missing clear operation

partition
       incorrect P.size(x) after split operations

graph
       problem with graph::clear() and destructor in presence
       of hidden nodes or edges

node/edge/face_map
       memory leak  fixed



TRIANGULATE_POLYGON  
       crashed if input size < 2, 
       inner & outer edges exchanged


GraphWin:
       opening context menu crashed after removing items of main menu removed
       memory leak in gw.clear_graph() fixed



------------------------------------------------------------------------------
LEDA-4.1
------------------------------------------------------------------------------

General Fixes
        name clash with __volatile under FreeBSD

Multi-Thread  (-DLEDA_MULTI_THREAD)
        problem in <LEDA/thread/mem_mgment.h>: used "string" but did
        not include <LEDA/string.h>

Numbers
       some minor fixes in _real.c

int_set
       bug on 64-bit platforms fixed

Sortseq
       reverse iteration (forall_rev_items) did not work

Demos
       demo_cout/DataTypes/sortseq_merge.c :  name clash with "quad"
       demo_cout/Impl/p_queue_test.c       :  f_heap redefined

GRAPH<vtype,etype>
       bug in operator= (not guarded against self-assignment) fixed

GraphWin
       error in gw_add_call template fixed

d3_ray.h
       missing prefixing macros


------------------------------------------------------------------------------
LEDA-4.0
------------------------------------------------------------------------------

prefixing:
   missing prefixing macros in <LEDA/d3_hull.h>

linux: 
   replaced setfpucw by corresponding assembler command

Makefiles:
   clean and del targets did not work properly for demo and test subdirectories
   man target: added -o to dvips to prevent sending the output to the printer


integer:
   memory leak in integer::divide fixed

rat_vector:
   constructor rat_vector(rational,rational) was declared but not defined

map:
   forall_defined iteration works for integer and pointer types


(rat_)polygon:
   missing implementation of operator==

(rat_)point_set:
   lookup crashed on empty point_set

window:
   ALT-<chr> shortcuts did not work for linux/X11
   After >>-input the frame label was always reset to the LEDA 
   copyright string ignoring the label defined by W.set_frame_label().


GraphWin:
   gw.win_init(x0,x1,y0) failed if called before gw.display()
   memory leak in read and read_gml fixed
   bug in write_ps (ghost edges) fixed
   memory leak in clear (if called from graph menu)



------------------------------------------------------------------------------
LEDA-3.8
------------------------------------------------------------------------------

graph::hide/restore_edge(e)
   now can be called in forall_edges(e,G) - Loops

graph iterator demo
   gw_git_demo.c caused internal error in egcs 1.1.x

graph::move_edge
   did not work for selfloops

cmp-based data types (dictionary, p_queue, sortseq ...)
   memory leak: dynamically allocated cmp-object not deleted

random_source:
   operator()(int bits) did only produce bits-1 random bits

integer:
   integer::random(int bits) every 32-th bit was zero

prefixing:
   missing prefixing macros in <LEDA/list.h>

partition:
   iteration did not work
   missing const qualifiers

graph_misc:
    Make_Simple did not find (and remove) parallel edges in undirected graphs
  

point_set:
   missing const qualifiers for point_set::inf and point_set::key

ALL_PAIRS_SHORTEST_PATHS
   did not work for undirected graphs (because of a selfloop), now does.

DIJKSTRA(G,s,t,...)
   had a memory leak (node_pq's not deleted)

rat_circle:
   bug in point_on_circle fixed

graphwin:
   color "invisible" could not be represented in gml format
   postscript output: incorrect bounding box
   read_gml: changed y-coordinates of nodes


------------------------------------------------------------------------------
LEDA-3.7.1
------------------------------------------------------------------------------

map2
    bug in copy constructor fixed

array2
    memory leak in operator=

d_array
   assignment did not copy default entry

leda_cmp_base (dictionary, p_queue, sortseq, ...)
    cmp_ptr pointed to deleted object after copy construction or
    assignment

Is_Biconnected/Is_Triconnected:
    did not work correctly in presence of selfloops

window
    uncatched overflow in W.message()

d3_window
    memory leak

graphwin:
    gw.acknowledge(...)  could not be called in handler functions
    place_into_box/win: division by zero for horizontal/vertical graphs 

graph_alg
    bug in MAX_CARD_MATCHING (non-initialized node_array)
    bug in MAX_FLOW (illegal memory access in level_queue)

face_map, edge_set, node_map2
    mising copy constructor and assignment operator

node_pq
    find_min() crashed on empty queue

d3_point, d3_rat_point
    incorrect orientation predicate (flipped sign)
    error in point_on_positive_side

d3_(rat_)plane
    missing constructor d3_(rat_)plane(const point&, const point&) added

d3_rat_plane
    bug in "normal_project" caused errors in "sqr_dist" and "reflect"

d3_hull
    incorrect orientation of initial triangle (caused crashes for some inputs)

set
    bug in stl-style iterator access

prefixing
    several missing type names added to (RE/UN)DEFINE_NAMES.h


------------------------------------------------------------------------------
LEDA-3.7 
------------------------------------------------------------------------------

CONVEX_HULL:
   did not work correctly for collinear points

dictionary:
   bug in ab_tree copy constructor and assignment operator fixed

segment:
   missing definition of s.distance() (distance from origin) added

ray:
   precision problem in r.intersection(segment) fixed

p_dictionary:
   missing implementation of D.del_item(it) added
   insert did not change information if key already present

map:
   M.defined(x) returned always true for x = current table size

graph:
 - forall macros did not work in presence of -DLEDA_PREFIX
 - memory leak in GRAPH<vtype,etype>::read() (for non-simple types vtype/etype)
 - I/O for parameterized graphs with type parameter "bool" did not work
 - copy constructor and assignment (copy_graph) destroyed ordering of 
   incoming edges

integer:
   bug in I/O functions on 64-bit systems

delaunay_triang:
   bug in constructor delaunay_triang(const list<point>&) 
   (missing initializations)


------------------------------------------------------------------------------
LEDA-3.6.1 
------------------------------------------------------------------------------

FIVE_COLOR:
    now can handle graphs with parallel or bidirected edges

bigfloat/real
    did not work on 64 bit systems (irix64)

array::binary_search
    was not declared "const"; now is

random_planar_graph(graph& G, int n)
    ocasionally crashed

graph::split_face
    did not update size of faces

list::contents(list_item)
    used non-const access (replaced LEDA_ACCESS by LEDA_CONST_ACCESS)

array::binary_search
    illegal memory access

d3_(rat_)point
    bug in contained_in_simplex

map2
    illegal memory access in operator()

read_directory
    forgot to close directory structure

bin_tree
    bug in copy_tree (pointer into freed memory)

memory_manager
    allignment bug (caused crash when using large matrices)

node_pq
    illegal memory access in P.prio(it) fixed

CLOSEST_PAIR:
    illegal array access fixed

window
   w.read_event(...) returned "no_event" for motion events inside of
   the panel area instead of ignoring them  (fixed)

GraphWin
    - editing (setup) of data labels for nodes and edges did not work
    - loading of undirected graphs now works (produced "cannot merge
      directed with undirecte graph" error message before)
    - (un)selecting nodes by clicking and dragging a rectangle with the
      middle button did only work if dragged from the lower left to
      the upper right corner.
    - context menues were not fully displayed when opened near the lower
      edge of the window


------------------------------------------------------------------------------
LEDA-3.6 
------------------------------------------------------------------------------

- subdivision::locate_point
    was completely broken

- array<T>::sort()
    illegal memory access (for class types T) 

- integer
    integer::div  (incorrect size of quotient)
    integer::ceil 
    integer::islong

- polygon::intersect(polygon) and unite
    still had bugs, now is based on a new algorithm using planar maps

- b_heap
    bug in decrease_key  (incorrect computation of max/min index)

- window
    very slow opening of windows and panels was caused by repeated
    construction of icons (even for windows that did not use icons)

    in action functions attached to buttons drawing mode was always
    set to xor_mode (now the mode is not changed)

- color
    made get-functions const
    included color into the name redefine procedure


- graphwin
    crashed when writing a postscript file of a graph without edges
    did not draw edge labels in postscript output

- edge_set
    missing iteration functions added (now forall(e,S) works)

- mem_mgment.h (multi-thread save memory manager)
    syntax error (missing \) corrected


------------------------------------------------------------------------------
LEDA-3.5.2 
------------------------------------------------------------------------------

- array
     forall(x,A) did not work with hpuxc++

- graph::read
     now can read old graph format (without reversals)
     restriction of label size to 1024 bytes eliminated

- GRAPH<T1,T2>::read
     null pointer reference

- array2::operator=
     did not allocate space for new table

- node_pq::del_min 
     crashed for emtpy queue

- bug in handle_base destructor and operator= in presence of -DMULTI_THREAD

- array
     memory leak in operator=

- Dictionaries with implementation parameter: _dictionary<K,I,impl>
     did not work for impl = ch_hash (missing equal_key function)

- Memory Management 
     did not compile with -DMULTI_THREAD

- bounded queues
     b_queue<T> Q(n)  could only contain n-1 elements

- forall_rev_items
     did NOT traverse the items in reversed order

- GraphWin
     could not save or read paramaterized graphs (GRAPH<T1,T2>)

- window
     W.create_pixrect(xpm_data) did not work for "chars_per_pixel > 1"

- d3_(rat_)plane
     missing default constructor definition



------------------------------------------------------------------------------
LEDA-3.5.1 
------------------------------------------------------------------------------

-  hide_edge/restore edge (many problems, documentation bug)

   There was a change in the semantics of G.hide_edge(e) from Version 3.4
   to Verson 3.5: 

     G.hide_edge(e)  
        removes e from the corresponding adjaceny lists
        AND from the list of all edges E

   The old definition of hide_edge (removed e only from the adjacency lists)
   caused a lot of problems with algorithms working on the global edge
   list of a graph. So, we decided that G.hide_edge(e) should completely
   hide e, i.e., temporarily have the same effect as G.del_edge(e).


   In previous version (< 3.5) the fact that hidden edges remained
   in the list of all edges was used to restore all hidden edges as in

       forall_edges(e,G) G.restore_edge(e);

   Now you must either use the restore_all operation

       G.restore_all_edges();

   or collect all hidden edges in a list, say hidden, and use

       forall(e,hidden) G.restore_edge(e);


   However, LEDA-3.5 had a bug just in graph::restore_all_edges() so 
   that only the second alternative worked. The bug is fixed in 3.5.1.


   Another problem caused by the fact that hidden edges now
   are removed from the global edge list was that the loop

      forall_edges(e,G) G.hide_edge(e)

   did not work anymore. This has also been fixed in LEDA-3.5.1
   



- integer::tostring  
     (did not allocate enough memory)

- list::reverse_items(it1,it2)
     (only reversed sub-list [it1,...,pred(it2)], now reverses [it1,...it2]) 

- int_set
     (memory leak fixed)

- graph::restore_all_edges()
     (restored only one edge)

- graph::write/graph::read 
     (now also write and read the reversal information of edges)

- graph: forall_edges/forall_nodes/forall_adj ...
     (deleting nodes/edges or hiding edges now works in forall loops)

- graph: forall_inout_edges
     (break now works as expected)

- node/edge_map::init()
     (unitialized memory caused crash in destructor)

- node_set/edge_set
     (declared member(x) as const, replaced array by map)

- Is_Simple(const graph&)
     (crashed when called for empty graph)

- Make_Biconnected
     (did not work for graphs with self-loops)

- polygon::intersection(line/segment)
     (computed multiple points if line/segment passed through vertex)

- polygon::intersection(polygon)/polygon::translate(...)
     (bug in translate that caused crash in intersection fixed)

- polygon::inside(point)
     (produced inconsistent results for points on the boundary of the polygon,
      now returns true for boundary points)

- SMALLEST_ENCLOSING_CIRCLE
     (error if all points are cocircular)

- TRIANGULATE_POINTS (-->SMALLEST_ENCLOSING_CIRCLE) 
     (crashed when called for a single point)

- SEGMENT_INTERSECTION
     (definition was missing)

- x11 (colors)
     (bug in x_new_color: returned incorrect color id)

- GraphWin
    (set_flush, set_node_width, set_node_height worked only after gw.display())

- Redefine/Undefine Names (leda_ - prefix)
     (did not work with graphwin.h, ps_file.h )


------------------------------------------------------------------------------
LEDA-3.5 
------------------------------------------------------------------------------

 - bug in point::angle(q,r) (now reports an error for degenerate inputs)

 - bug in ch_hash::insert (returned illegal pointer)

 - bug in segment::distance(point) fixed  and missing
   rat_segment::sqr_distance(rat_point) inserted

 - bug in operator>>(random_source&,integer&)

 - bug in vector::operator=  (assignment of zero-dimensional vector)

 - missing copy constructor and assignment operator for node/edge_map

 - param_types.h: declared some of the GenPtr variables as "volatile"

 - problems when including string.h before any other header file

 - bug in graph::del_edge(e) for hidden edge e (incorrect degree of source)  

 - bug in leda_copy (missing initialization in non-template versions)

 - bug in window::choice_item() (for fixed (6,7,8) numbers of strings)

 - bug in node_set  (missing copy constructor and assignment operator)

 - bug in polygon::unit() fixed

 - bug in MAXFLOW (in presence of zero capacity edges) fixed

 - bug in VORONOI (wrong edge labels)

 - bug in set<T> symdiff operator  (% and %=)

 - bug in list::move_to_rear

 - PLANAR replaced by PLANAR0

 - bug in circle output/input operators fixed 

 - bug in straight line embedding algorithms (did not work for n < 3) 

 - bug in skilist memory allocation on 64bit machines

 - PLANAR_MAP::split_edge(edge e, vtype x)
   tried to assign node info x to an edge  

 - missing initialization in "triangulated_planar_graph"

 - bug in k_heap (parent computation failed for root)

------------------------------------------------------------------------------
LEDA-3.4.1 
------------------------------------------------------------------------------

 New (beta) version of GraphWin (see .../src/graphwin/Changes)

 Bug in PLANAR_MAP constructors fixed

 Bug in random_planar_graph fixed

 Bug in Is_Biconnected fixed

 changed type of arguments in Is_...(G) (graph_misc.h) to "const graph&"

 name conflict with "mutex":  renamed mutex to leda_mutex

 _os2.c : Makefile fixed and missing bitmap operations added

 polygon/rat_polygon  several bugs (union,area,...)            FIXED

 graph::size(face) always returned 0                           FIXED

 graph::write() produced self-loops for undirected graphs      FIXED

 INT<cmp> name conflicts with MFC                              FIXED

 array<int>::sort(cmp)  ignored cmp function                   FIXED  

 graph::compute_faces() did not delete existing list of faces  FIXED

 list::rank()  did not work at all                             FIXED      

 window::string_item()  did not update string length           FIXED
                        now strings can bed edited using
                        mouse and cursor keys

------------------------------------------------------------------------------
LEDA-3.4-p1  (patch1) 
------------------------------------------------------------------------------

- work-around for hpc++ bug:

    new versions of rat_vector.h und _rat_vector.c
    (moved constructors into c-file)
    inserted some casts from integer to rational in _rational.c

- missing }*/ in bigfloat.h ( after todouble() ) inserted


- real.h
   made sign(real) inline


------------------------------------------------------------------------------
LEDA-3.4 (02.09.1996)
------------------------------------------------------------------------------

the following problems have been fixed:

- Color allocation problem

- memory problem in graph

- round for rationals

- rotation bug in rb_tree

- uninitialized memory

- missing constructors for p_queue and r_heap

- bug in k_heap for  k>2   

- shared libs for LINUX  

- Bug in hashing

- Bug in panel::int_item("...",x,1,1);  

- Bug in integer bitwise or                             

- Bug in line::perpendicular 

- Bug im sweep Algorihtmus

- Bug Tree Collection

- Bug when using colors without opening window

- problem with m_heap::print

- Iterators and g++ warnings


------------------------------------------------------------------------------
LEDA-3.3.1 (09.04.1996)
------------------------------------------------------------------------------

BUG: lconfig script 

FIX: replace in lines 104 and 107 of <LEDA>/lconfig 
     src/Make.pro by prog/Make.pro


BUG: memory leak in graph copy constructor and assignment

FIX: delete or comment out lines 70 and 77 in <LEDA>/src/_graph.c
     (70)  memory_allocate_block(sizeof(node_struct),n);
     (77)  memory_allocate_block(sizeof(edge_struct),m);


BUG: window destructor should be declared virtual 

FIX: replace in line 288 of <LEDA>/incl/LEDA/base_window.h
        ~BASE_WINDOW();
     by
        virtual ~BASE_WINDOW();


BUG: planar_map(const planar_map&) copy constructor missing

FIX: insert after line 140 in <LEDA>/incl/LEDA/planar_map.h the line
        planar_map(const planar_map& M) : graph(M) { make_planar_map(); }


BUG: memory leak in Karatsuba multiplication (_integer.c)

FIX: insert in <LEDA>/src/numbers/_integer.c after line 813 the line
       delete[] trp;


BUG: problem with grid_mode cursor in windows in presence of 
     other (panel) windows

FIX: insert in file <LEDA>/src/window/_base_window.c the following 
     two lines at the beginning of  function void BASE_WINDOW::cursor(void) 

     if (this != read_window) return;
     x_set_read_gc(draw_win);



PROBLEM: "shadow" warnings by g++ (2.7.2)

FIX:     remove the definition of the __NEW_SCOPE_RULES__ macro 
         in <LEDA/system.h>



BUG: error in gen_array::binary_search

FIX: replace in <LEDA>/src/basic/_array.c the gen_array::binary_search  by

int gen_array::binary_search(GenPtr x)
{ int l = 0;
  int r = sz-1;
 
  if (int_type())
    { int x_i = LEDA_ACCESS(int,x);
      while (l <= r)
      { int m = (l+r)/2;
        int m_i = LEDA_ACCESS(int,v[m]);
        if (x_i == m_i) return m+Low;
        if (x_i > m_i)
           l = m+1;
        else
           r = m-1;
       }
     }
  else
     while (l <= r)
     { int m = (l+r)/2;
       int c = cmp(x,v[m]);
       if (c == 0) return m+Low;
       if (c > 0)
          l = m+1;
       else
          r = m-1;
      }
 
  return  Low-1;
}



PROBLEM: conflicts with "node_data" and "edge_data" macros
         in REDEFINE_NAMES.h and <LEDA/node/edge_map.h>

FIX:     delete all occurences of these two macros



PROBLEM: cannot construct and delete interval sets in the dynamic memory
         using the new and delete operators

FIX:     remove "LEDA_MEMORY(range_tree)" from <LEDA/impl/range_tree.h>



PROBLEM: compilation problems with microsoft visual c++

FIX:     replace <strstream.h> by <strstrea.h>, undefine __TEMPLATE_FUNCTIONS__
         in <LEDA/system.h>,  use /c option before /Tp option in make.src



PROBLEM: missing documentation of set join,intersect,difference operations
FIX:     added manual descriptions in <LEDA/set.h>


PROBLEM: output statement (cout << ...) in _rational.c
FIX:     remove it



PROBLEM: memory leak in graph::clear()
FIX:     replace in <LEDA>/src/graph/_graph.c line  193
            forall(v,v_list) delete v;
         by
            forall(v,v_free) delete v;

PROBLEM: plan_demo program crashes in presence of a K5 Kuratowski graph
FIX:     substitute in file prog/demo/plan_demo.c line 342
           forall_nodes(v,G) if (G.degree(v) == 3) break;
         by
           forall_nodes(v,G) 
              if (v == G.last_node() || G.degree(v) == 3) break;
     
------------------------------------------------------------------------------
 LEDA-3.3 (15.02.96)
------------------------------------------------------------------------------

Bugs have been fixed in

- basic
     string::operator[](int)
     string::string(const char*, const char*)
     real/bigfloat (pow2 problem)
     integer::random

- dictionaries
     h_array 
     map

- graph
    read/write
    copy_graph
    operator=
    make_directed()
    clear
    generators

- planar_map
    operator=
    copy constructor

-graph_alg
    bellman_ford
    planarity test
    min_cut

-geometry
    rat_point
    circle::intersection
    line::perpendicular
    segment::intersection
    polygon::unite
    DELAUNAY_TRIANG

- windows 
    panel string item
    nested panels (menues)

- installation
    problem with REDEFINE.h fixed



------------------------------------------------------------------------------
 LEDA  3.2.3  (18.9.95)
------------------------------------------------------------------------------

- bug in sweep_segments fixed
- missing initialization in function template "Convert"
- bug in string::operator[] fixed
- bug in integer cmp fixed


------------------------------------------------------------------------------
 LEDA  3.2.2  (01.9.95)
------------------------------------------------------------------------------

- node_pq::member   returned always true
- rat_segment::intersection(rat_segment)
- intersection(rat_segment,rat_segment)  for vertical segments
- array2: missing copy-constructor and assignment operator inserted
- ugraph::first_adj_edge(node v)
- ugraph::last_adj_edge(node v)
- point,rat_point,segment,rat_segment (sign of the orientation primitive)
- h_array (empty array now has default size of 1 instead of 512)
- polygon::unite


------------------------------------------------------------------------------
 LEDA  3.2.1 (27.7.95)
------------------------------------------------------------------------------

 - segment: orientation
 - missing destructor for handle_base
 - forall - macro 
 - list::split operation 
 - iteration for constant sets
 - bug in MIN_CUT graph algorithm 
 - bug in orientation(segment,point) 
 - polygon::intersection and polygon::inside rewritten
 - bug in window grid drawing


------------------------------------------------------------------------------
 LEDA  3.2    (7.7.95)
------------------------------------------------------------------------------


- SEGMENT_INTERSECTION

            now also works in case of "degenerate" input

- graphs
            graph::cyclic_in_succ, graph::cyclic_in_pred,
            graph::first_adj_edge, and graph::last_adj_edge fixed

            new_edge(e1,e2,dir1,dir2) fixed

            copy constructor and assingment now preserve order of 
            adjacency lists

            missing implementation of graph::in_edges(v) included

            bug in copy constructor of node/edge_array and node/edge_map fixed

            b_node_pq: first insert now initalizes minimum correctly

            planar_map::split_edge fixed
  


- param_types
             one-word class types
             64 bit architectures

- h_array
            iteration (forall_defined) now works

- set
           copy constructor and operator=
           (bug in bin_tree::copy_tree fixed)


- map<I,E>  destructor now deletes E's
            bug in rehash fixed

- array
            array::read(istream in) replaced by  array::read(istream& in)

- panel
            panel("...",w,h)   now creates a panel with width w and height h

 
- skiplist  change_inf now destroys old and copies new information
 
- matrix    memory leak in triang fixed




------------------------------------------------------------------------------
Version 3.1.2       (3.02.95)
------------------------------------------------------------------------------

-list.h:   made list_item list::operator[](int i)  const
-string.h: made operator+ a friend function
-map.h:    replace int(x)   by  int(Convert(x))
-graph.h:  replace in line 258 and 268 "next_power(i)"  by "next_power(i+1)"
-integer.c: replace line 1752 { cout << "0"; by { out << "0";
            replace line 1769 if (x.PTR->sign == NEGATIVE) cout << "-";
-real.c: many changes

SUNPRO C++ (use 4.0.1 NOT 4.0, use -pto flag )
- do not use assembler code in _string.c
- define __svr4__ if __SVR4 is defined
- use format_string variant of string constructor
- changes to avoid some of the "something hides something" warnings

------------------------------------------------------------------------------
Version 3.1.1       (27.01.95)
------------------------------------------------------------------------------

 array.h:     operator[] now calls gen_array::entry (instead of inf)
 edge_set.h:  node_array<list_item> replaced by edge_array<list_item>
 list.h:      cmp_ptr set to nil in list::search()
 list.h:      missing app - function inserted.
 node_pq.h    print_inf  now prints index of node
 dlist.h:     replaced EOF by char(EOF) (problems with EOF <0)
 _g_inout.c:  read & write for user defined node/edge types fixed
 _g_update.c: infinite loop in insert_reverse_edges eliminated
 _skiplist.c: locate_succ, locate fixed
 _integer.c:  memory leak in integert:integer(double) fixed
 _real.c:     special floating point functions calls replaced
 _random.c:   BSD Code for random/srandom included 
 _basic.c:    usleep replaced by sleep
 _g_map.c:    table is deleted only if table_size > 0
 _bin_tree.c: copy constructor now sets corr-pointer of rightmost leaf
 Type_Name function defined for basic LEDA types (point,string, ...)

 Makefiles: _sparc.s will be assembled only on sparc machines

------------------------------------------------------------------------------
Version 3.1
------------------------------------------------------------------------------

16.01.95    array::operator=  fixed

13.01.95    graph::read and graph::write did not work for unparameterized
            graphs, fixed. 

13.01.95    node_set edge_set rewritten
            int_set: hard coded word size replaced by sizeof-call

 6.01.95    list<T>::sort(cmp_func), list<T>::bucket_sort(ord_func)
            list<T>::min(cmp_func), list<T>::max(cmp_func), 
            list<T>::apply(app_func) did not work for types with
            sizof(T) > sizeof(void*); bug is fixed.

            array::sort(cmp_func), array::sort(l,h,cmp_func)
            array::binary_search(cmp_func), same problem as in lists fixed

21.11.94    bug in vector::operator=(const vector&) fixed
            (old (d) and new (n) dimensions exchanged)

17.11.94    bug in rs_tree (set<T>) copy constructor fixed

15.11.94    LEDA_MEMORY: operator new & delete now use the size argument 

07.10.94    bug in array copy constructor fixed
            memory leak in list::assign() fixed
            polygon CONVEX_HULL(list<point>)  new algorithm (Graham's Scan)
            bugs in segment::intersection() and line::intersection() fixed
        
29.09.94    bug in binary heaps (negative integer keys) fixed

28.09.94    UGRAPH::assign(node/edge,...) fixed

 6.09.94    bug in list<node> graph::adj_nodes() (undirected graphs) fixed 

 8.08.94    Iteration (forall_defined) for h_arrays 

 4.08.94    some problems in _leda_panel.c fixed (slider items, buttons, ...)

11.07.94    Multi-definition problem with read_mouse(window, ...) and g++ fixed

22.03.94    bug in skiplist copy constructor fixed

22.12.93    memory leaks in leda panels 

21.12.93    nested forall-loops

17.12.93    string::read now can read strings of arbitrary length

11.10.93    made dlist::bucket_sort stable
            corrected return value of COMPUTE_CORRESPONDENCE 

08.09.93    memory bug in dp_hash (dynamic perfect hashing) fixed

12.08.93    k_heap::del_item fixed 

25.06.93    made rs_tree::change_inf (dictionary) clear old and copy new 
            information 

16.06.93    dlist::search (replaced != by call of virtual cmp function)

07.06.93    line::intersection (used to report intersection of parallel lines)

01.06.93    fixed bug in queue::append (replaced Convert by Copy)

05.05.93    bugs in MAX_WEIGHT_BIPARTITE_MATCHING fixed (by M. Paul)

05.04.93    prio.h: added missing ostream argument cout to Print calls

12.03.93    stack::push(x)    replaced Convert(x) by Copy(x)

09.03.93    segment::angle()  returns zero for segments of length zero

05.03.93    memory leak in draw_(filled_)polygon fixed

25.01.93    bug in ab_tree::clear() fixed (forgot to set counter to zero)

30.12.92    made dlist update operations protected

20.12.92    changed type "SIG_PF" in basic.h to "LEDA_SIG_PF"

07.12.92    missing operation ugraph::read(istream&) inserted



------------------------------------------------------------------------------
Version 3.0
------------------------------------------------------------------------------

09.11.92    Convert and Access for parameter types of size smaller than 
            pointers (e.g. char, short) fixed

16.07.92    bug with colinear points in delaunay_tree, VORONOI, point_set, ...
            fixed

27.05.92    MAX_WEIGHT_BIPARTITE_MATCHING(double) (_mwb_matching.c)
            fixed precicision problem that caused a negative loop in DIJKSTRA

19.05.92    list::sort now works for lists of length 1

12.05.92    type conversion for "char" (Copy,Convert,Access, ...)  fixed


------------------------------------------------------------------------------
Version 2.2
------------------------------------------------------------------------------

27.04.92    matrix::operator=(const matrix&) 
            matrix::triang()

17.04.92    lost memory bug in string::operator+ fixed   (Nicolas Caillaud)

16.04.92    made all destructors virtual

13.04.92    bug in GRAPH::assign(node/edge,vtype/etype) fixed
            made operator<< and operator>> for circles reverse ops

11.04.92    copy-bug in graph::operator=() and graph(const graph&) fixed


------------------------------------------------------------------------------
Version 2.1
------------------------------------------------------------------------------

16.12.91    fixed Copy bug for list, GRAPH, and UGRAPH

10.12.91    defined read(write)_node(edge)_entry for UGRAPH


28.11.91    made void*-functions (append,push, ....) in dlist, graph
            and ugraph protected

12.11.91    vector/matrix subtypes for arrays
            operator=  & operator== now may be called for objects with
            differnt dimensions


11.11.91    Copy(vector&) ---> Copy(const vector&)
            Copy(matrix&) ---> Copy(const matrix&)


31.10.91    string& string::operator=(const char* s)
            Bug: Zugriff auf deallocierten Speicher fuer p->s = s


28.10.91    in bool line::operator==(const line&)
            Bug: funktionierte nicht fuer 2 vertikale Linien

