Submission #8325611


Source Code Expand

#include <algorithm>
#include <cassert>
#include <cmath>
#include <iomanip>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <string>
#include <utility>
#include <vector>

using namespace std;
using ll = long long;

constexpr ll infl = 10000000000000007LL;
constexpr int inf = 1000000007;

// 1から番号が始まっていることに注意
class UnionFind {
    vector<int> parent;
    vector<int> rank;

public:
    int root(int x) {
        return parent[x] >= 0 ? parent[x] = root(parent[x]) : x;
    }

    void unite(int x, int y) {
        int rootX = root(x);
        int rootY = root(y);
        if (rootX == rootY)
            return;

        if (rank[rootX] > rank[rootY]) {
            parent[rootX] += parent[rootY];
            parent[rootY] = rootX;
        } else {
            if (rank[rootX] == rank[rootY])
                ++rank[rootY];

            parent[rootY] += parent[rootX];
            parent[rootX] = rootY;
        }
    }

    bool same(int x, int y) {
        return root(x) == root(y);
    }

    int groupSize(int x) {
        return -parent[root(x)];
    }

    int numGroup() {
        int num = 0;
        for (int k : parent) {
            num += k < 0;
        }
        return num;
    }

    UnionFind(int size) : parent(size + 1, -1), rank(size + 1, 1) {
        parent[0] = rank[0] = 0;
    }
};

int main() {
    int n, m;
    cin >> n >> m;
    vector<int> idx(n + 1);
    for (int i = 1; i <= n; ++i) {
        int p;
        cin >> p;
        idx[p] = i;
    }

    UnionFind uf(n);
    for (int i = 0; i < m; ++i) {
        int x, y;
        cin >> x >> y;
        uf.unite(x, y);
    }

    int ans = 0;
    for (int i = 1; i <= n; ++i) {
        ans += uf.same(i, idx[i]);
    }

    cout << ans << endl;
    return 0;
}

Submission Info

Submission Time
Task D - Equals
User rimol
Language C++14 (GCC 5.4.1)
Score 400
Code Size 1911 Byte
Status AC
Exec Time 88 ms
Memory 1408 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 400 / 400
Status
AC × 4
AC × 23
Set Name Test Cases
Sample 0_000.txt, 0_001.txt, 0_002.txt, 0_003.txt
All 0_000.txt, 0_001.txt, 0_002.txt, 0_003.txt, 1_004.txt, 1_005.txt, 1_006.txt, 1_007.txt, 1_008.txt, 1_009.txt, 1_010.txt, 1_011.txt, 1_012.txt, 1_013.txt, 1_014.txt, 1_015.txt, 1_016.txt, 1_017.txt, 1_018.txt, 1_019.txt, 1_020.txt, 1_021.txt, 1_022.txt
Case Name Status Exec Time Memory
0_000.txt AC 1 ms 256 KB
0_001.txt AC 1 ms 256 KB
0_002.txt AC 1 ms 256 KB
0_003.txt AC 1 ms 256 KB
1_004.txt AC 44 ms 256 KB
1_005.txt AC 84 ms 1408 KB
1_006.txt AC 88 ms 1408 KB
1_007.txt AC 1 ms 256 KB
1_008.txt AC 1 ms 256 KB
1_009.txt AC 1 ms 256 KB
1_010.txt AC 1 ms 256 KB
1_011.txt AC 1 ms 256 KB
1_012.txt AC 1 ms 256 KB
1_013.txt AC 2 ms 256 KB
1_014.txt AC 3 ms 256 KB
1_015.txt AC 1 ms 256 KB
1_016.txt AC 1 ms 256 KB
1_017.txt AC 2 ms 256 KB
1_018.txt AC 39 ms 256 KB
1_019.txt AC 30 ms 1408 KB
1_020.txt AC 30 ms 1408 KB
1_021.txt AC 30 ms 1408 KB
1_022.txt AC 88 ms 1408 KB