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git://git.tartarus.org/simon/puzzles.git
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Files
414330d9ad
or two, a debugging fix, a couple of explicit initialisations of variables that were previously read uninitialised, and a fix for a whopping great big memory leak in Slant owing to me having completely forgotten to write free_game(). [originally from svn r6159]
31 lines
521 B
C
31 lines
521 B
C
/*
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* dsf.c: two small functions to handle a disjoint set forest,
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* which is a data structure useful in any solver which has to
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* worry about avoiding closed loops.
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*/
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#include "puzzles.h"
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int dsf_canonify(int *dsf, int val)
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{
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int v2 = val;
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while (dsf[val] != val)
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val = dsf[val];
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while (v2 != val) {
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int tmp = dsf[v2];
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dsf[v2] = val;
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v2 = tmp;
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}
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return val;
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}
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void dsf_merge(int *dsf, int v1, int v2)
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{
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v1 = dsf_canonify(dsf, v1);
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v2 = dsf_canonify(dsf, v2);
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dsf[v2] = v1;
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}
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