[백준] 10451번 : 순열 사이클

10451번: 순열 사이클

 

#include <iostream>
#include<vector>
#include<string>
#include<queue>
#define MAX 1001
using namespace std;

int g[MAX];
int visit[MAX];
int cycle = 0;

void dfs(int x) {
	if (visit[x] == true) {
		cycle++;
		return;
	}
	visit[x] = true;
	dfs(g[x]);
}

int main() {

	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int t,T, n;

	cin >> T;
	while (T--) {
		cin >> t;
		cycle = 0;

		for (int i = 1;i <= t;i++) {
			g[i] = 0;
			visit[i] = 0;
		}

		for (int i = 0;i < t;i++) {
			cin >> n;
			g[i + 1]=n;
		}

		for (int i = 1;i <= t;i++) {
			if (visit[i] == true) continue;
			dfs(i);
		}
		cout << cycle << '\n';
	}
	return 0;
}