Submission #891048

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Source Code Expand

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;
typedef pair<int,int> PII;

int main() {
	int N;
	cin >> N;
	vector<int> input;
	for(int i=0; i<N; i++) {
		int p;
		cin >> p;
		input.push_back(p-1);
	}
	int cnt = 0;
	for(int i=0; i<N; i++)
		if( i == input[input[i]])
			cnt++;
	cnt /= 2;
	cout << cnt << endl;
	return 0;
}

Submission Info

Judge Result