Create union-find_disjoint_set.cpp

Changes

1 changed files (+20/-0)

• Data Structures/union-find_disjoint_set.cpp (new)
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    + #include <vector> + using namespace std; + + class UFDS { + private: vector<int> p, rank; + public: + UFDS(int N) { + p.assign(N, 0); + for (int i = 0; i < N; i++) p[i] = i; + rank.assign(N, 0); + } + int find_set(int i) { return (p[i] == i) ? i : (p[i] = find_set(p[i])); } + bool same_set(int i, int j) { return find_set(i) == find_set(j); } + void union_set(int i, int j) { + if (same_set(i, j)) return; + int x = find_set(i), y = find_set(j); + rank[x] > rank[y] ? p[y] = x : p[x] = y; + if (rank[x] == rank[y]) rank[y]++; + } + };