39 lines
702 B
Java
39 lines
702 B
Java
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public class DisjointSetsRank {
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int[] p;
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int[] rank;
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public DisjointSetsRank(int size) {
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p = new int[size];
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for (int i = 0; i < size; i++)
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p[i] = i;
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rank = new int[size];
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}
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public int root(int x) {
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return x == p[x] ? x : (p[x] = root(p[x]));
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}
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public void unite(int a, int b) {
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a = root(a);
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b = root(b);
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if (a == b)
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return;
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if (rank[a] < rank[b]) {
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p[a] = b;
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} else {
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p[b] = a;
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if (rank[a] == rank[b])
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++rank[a];
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}
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}
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public static void main(String[] args) {
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DisjointSetsRank ds = new DisjointSetsRank(10);
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System.out.println(false == (ds.root(0) == ds.root(9)));
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ds.unite(0, 9);
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System.out.println(true == (ds.root(0) == ds.root(9)));
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}
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}
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