Submission #891173


Source Code Expand

#include<iostream>
#include<vector>
#include<string>
#include<array>
#include<algorithm>
#include<list>
#include<cmath>
#include<iomanip>
#include<queue>
#include<functional>
#include<climits>
#include<iterator>
#include<unordered_set>
#include<unordered_map>
#include<map>
#include<set>
#include<typeinfo>
using namespace std;

const double pi=4*atan(1.0);

constexpr long long mod=static_cast<long long>(1e9+7);

using cWeightEdges=vector<vector<pair<int,int>>>;
using cEdges=vector<vector<int>>;

int main() {
	int N;
	cin>>N;
	vector<int> a(N);
	for(auto& val:a){
		cin>>val;
		--val;
	}
	
	int ans=0;
	for(int i=0;i<N;++i){
		if(i==a[a[i]])++ans;
	}

	cout<<ans/2<<endl;
	//system("pause");
	return 0;
}

Submission Info

Submission Time
Task B - Friendly Rabbits
User HORI1991
Language C++14 (GCC 5.4.1)
Score 200
Code Size 751 Byte
Status AC
Exec Time 32 ms
Memory 640 KB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 200 / 200
Status
AC × 3
AC × 15
Set Name Test Cases
Sample 0_00.txt, 0_01.txt, 0_02.txt
All 0_00.txt, 0_01.txt, 0_02.txt, 1_00.txt, 1_01.txt, 1_02.txt, 1_03.txt, 1_04.txt, 1_05.txt, 1_06.txt, 1_07.txt, 1_08.txt, 1_09.txt, 1_10.txt, 1_11.txt
Case Name Status Exec Time Memory
0_00.txt AC 2 ms 256 KB
0_01.txt AC 2 ms 256 KB
0_02.txt AC 3 ms 256 KB
1_00.txt AC 2 ms 256 KB
1_01.txt AC 30 ms 640 KB
1_02.txt AC 30 ms 640 KB
1_03.txt AC 30 ms 640 KB
1_04.txt AC 32 ms 640 KB
1_05.txt AC 30 ms 640 KB
1_06.txt AC 30 ms 640 KB
1_07.txt AC 31 ms 640 KB
1_08.txt AC 13 ms 384 KB
1_09.txt AC 26 ms 512 KB
1_10.txt AC 22 ms 512 KB
1_11.txt AC 7 ms 256 KB