Submission #891057

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Source Code Expand

#include <iostream>
#include <vector>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    int N; cin >> N;
    vector<int> A(N, -1);
    int answer = 0;
    for (int i = 0; i < N; ++i) {
        cin >> A[i];
        --A[i];
        if (A[A[i]] == i)
            ++answer;
    }

    cout << answer << "\n";
}

Submission Info

Judge Result