Submission #891121

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Source Code Expand

#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <deque>
#include <complex>
#include <stack>
#include <queue>
#include <cstdio>
#include <cctype>
#include <cstring>
#include <ctime>
#include <iterator>
#include <bitset>
#include <numeric>
#include <list>
#include <iomanip>
#include <cassert>
#include <array>
#include <tuple>
#include <initializer_list>
#include <unordered_set>a#include <cstdlib>
#include <cmath>
#include <climits>
#include <cfloat>
#include <map>
#include <utility>
#include <set>
#include <iostream>
#include <memory>
#include <string>
#include <vector>
#include <algorithm>
#include <functional>
#include <sstream>
#include <deque>
#include <complex>
#include <stack>
#include <queue>
#include <cstdio>
#include <cctype>
#include <cstring>
#include <ctime>
#include <iterator>
#include <bitset>
#include <numeric>
#include <list>
#include <iomanip>
#include <cassert>
#include <array>
#include <tuple>
#include <initializer_list>
#include <unordered_set>
#include <unordered_map>
#include <forward_list>
using namespace std;
using ll = long long;
#define rep(i,n) for(int i = 0; i < (int)(n); ++i)

int n;
int a[100010];

int main() {
    while (cin >> n) {
        int ans = 0;
        for (int i = 0; i < n; i++) {
            cin >> a[i];
            --a[i];
        }
        for (int i = 0; i < n; i++) {
            if (a[a[i]] == i) {
                ++ans;
            }
        }
        cout << ans / 2 << endl;
    }
}

Submission Info

Compile Error

./Main.cpp:32:26: warning: extra tokens at end of #include directive
 #include <unordered_set>a#include <cstdlib>
                          ^
./Main.cpp:32:44: fatal error: unordered_set>: No such file or directory
 #include <unordered_set>a#include <cstdlib>
                                            ^
compilation terminated.