forked from bartvdbraak/blender
55 lines
655 B
C++
55 lines
655 B
C++
#include "UnionFind.h"
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#include <assert.h>
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int UnionFind::find(int x)
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{
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assert(x < m_N);
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assert(x >= 0);
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while (x != id[x])
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{
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x = id[x];
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assert(x < m_N);
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assert(x >= 0);
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}
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return x;
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}
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UnionFind::UnionFind(int N)
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:m_N(N)
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{
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id = new int[N]; sz = new int[N];
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reset();
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}
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void UnionFind::reset()
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{
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for (int i = 0; i < m_N; i++)
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{
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id[i] = i; sz[i] = 1;
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}
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}
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int UnionFind ::find(int p, int q)
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{
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return (find(p) == find(q));
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}
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void UnionFind ::unite(int p, int q)
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{
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int i = find(p), j = find(q);
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if (i == j)
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return;
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if (sz[i] < sz[j])
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{
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id[i] = j; sz[j] += sz[i];
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}
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else
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{
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id[j] = i; sz[i] += sz[j];
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}
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}
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