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* Mark many more function (and some objects) staticBen Harris2023-02-18
| | | | | | | | | | | | | I noticed commit db3b531e2cab765a00475054d2e9046c9d0437d3 in the history where Simon added a bunch of "static" qualifiers. That suggested that consistently marking internal functions "static" is desirable, so I tried a build using GCC's -Wmissing-declarations, which requires prior declaration (presumed to be in a header file) of all global functions. This commit makes the GTK build clean under GCC's -Wmissing-declarations. I've also adding "static" to a few obviously internal objects, but GCC doesn't complain about those so I certainly haven't got them all.
* Call deallocate() in matching.c test routinesBen Harris2023-02-18
| | | | | | | This is mostly so that the function is used at all, but I've also removed another memory leak from --autotest mode to make it apparently leak-free. The testing from standard input mode has more leaks than I want to fix.
* Use C99 bool within source modules.Simon Tatham2018-11-13
| | | | | | | | | | This is the main bulk of this boolification work, but although it's making the largest actual change, it should also be the least disruptive to anyone interacting with this code base downstream of me, because it doesn't modify any interface between modules: all the inter-module APIs were updated one by one in the previous commits. This just cleans up the code within each individual source file to use bool in place of int where I think that makes things clearer.
* Replace TRUE/FALSE with C99 true/false throughout.Simon Tatham2018-11-13
| | | | | | This commit removes the old #defines of TRUE and FALSE from puzzles.h, and does a mechanical search-and-replace throughout the code to replace them with the C99 standard lowercase spellings.
* Implementation of the Hopcroft-Karp algorithm.Simon Tatham2018-04-22
This is a dedicated algorithm for finding a maximal matching in a bipartite graph. Previously I've been solving that problem in this code base using maxflow.c, modelling the graph matching problem as a restricted case of the optimal network flow problem and then using a full-strength algorithm for the latter. That's overkill, and also algorithmically wasteful - the H-K algorithm is asymptotically better, because it can find multiple augmenting paths in each pass (hence getting the maximum benefit out of each expensive breadth-first search), as a consequence of not having to worry about lower- or higher-value augmenting paths in this restricted problem. So I expect this algorithm to be faster, at least in principle or in large cases, when it takes over the jobs currently being done by maxflow. But that's not the only benefit. Another is that the data representation is better suited to the problems actually being solved, which should simplify all the call sites; a third is that I've incorporated randomisation of the generated matching into the H-K module itself, which will further save effort at each call site because they will no longer have to worry about permuting the algorithm's input - they just have to pass it a random_state and it will take care of that internally. This commit only introduces the new matching.c and builds a test utility for it. I haven't yet migrated any clients of maxflow.