Submission #890975


Source Code Expand

#include<iostream>
#include<iomanip>
#include<map>
#include<unordered_map>
#include<set>
#include<unordered_set>
#include<vector>
#include<array>
#include<string>
#include<stack>
#include<queue>
#include<algorithm>
#include<cassert>
#include<functional>
#include<random>
#include<complex>
//#include<boost/multiprecision/cpp_int.hpp>
#define int int64_t
#define REP(i, a, b) for (int64_t i = (int64_t)(a); i < (int64_t)(b); i++)
#define rep(i, a) REP(i, 0, a)
#define EACH(i, a) for (auto i: a)
#define ITR(x, a) for (auto x = a.begin(); x != a.end(); x++)
#define ALL(a) (a.begin()), (a.end())
#define HAS(a, x) (a.find(x) != a.end())
#define Min(x) *min_element(ALL(x))
#define Max(x) *max_element(ALL(x))
#define Unique(L) (L.erase(unique(ALL(L)), L.end()))
using namespace std;
//typedef boost::multiprecision::cpp_int bigint;
const double EPS = 1e-9;
const double PI = acos(-1.0);


signed main(void) {
	cin.tie(0);
	ios::sync_with_stdio(false);

	int N;
	cin >> N;
	vector<int>a(N);
	rep(i, N)cin >> a[i];
	rep(i, N)a[i]--;

	int ans = 0;
	rep(i, N)if (a[a[i]] == i)ans++;
	cout << ans / 2 << endl;
}

Submission Info

Submission Time
Task B - Friendly Rabbits
User eukaryo
Language C++14 (GCC 5.4.1)
Score 200
Code Size 1152 Byte
Status AC
Exec Time 11 ms
Memory 1152 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 3 ms 256 KB
0_01.txt AC 3 ms 256 KB
0_02.txt AC 3 ms 256 KB
1_00.txt AC 3 ms 256 KB
1_01.txt AC 11 ms 1024 KB
1_02.txt AC 11 ms 1024 KB
1_03.txt AC 11 ms 1152 KB
1_04.txt AC 11 ms 1024 KB
1_05.txt AC 11 ms 1024 KB
1_06.txt AC 11 ms 1024 KB
1_07.txt AC 11 ms 1024 KB
1_08.txt AC 6 ms 512 KB
1_09.txt AC 10 ms 896 KB
1_10.txt AC 9 ms 768 KB
1_11.txt AC 4 ms 384 KB