48 lines
1.2 KiB
Text
48 lines
1.2 KiB
Text
/*
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Copyright (C) 2006 Pedro Felzenszwalb
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#ifndef DISJOINT_SET
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#define DISJOINT_SET
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// disjoint-set forests using union-by-rank and path compression (sort of).
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typedef struct {
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int rank;
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int p;
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int size;
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} uni_elt;
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class universe {
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public:
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universe(int elements);
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~universe();
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int find(int x);
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void join(int x, int y);
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int size(int x) const {
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return elts[x].size;
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}
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int num_sets() const {
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return num;
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}
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private:
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uni_elt *elts;
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int num;
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};
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#endif
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