Submission #513667

#	Time	Username	Problem	Language	Result	Execution time	Memory
513667		blue	Star triangles (IZhO11_triangle)	C++17	100 / 100	406 ms	13284 KiB

triangle

#include <iostream>
#include <map>
#include <vector>
using namespace std;

using ll = long long;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    map<int, ll> mx, my;

    int N;
    cin >> N;

    int X[1+N], Y[1+N];
    for(int i = 1; i <= N; i++)
    {
        cin >> X[i] >> Y[i];

        if(mx.find(X[i]) == mx.end()) mx[X[i]] = 1;
        else mx[X[i]]++;

        if(my.find(Y[i]) == my.end()) my[Y[i]] = 1;
        else my[Y[i]]++;
    }

    ll ans = 0;

    for(int i = 1; i <= N; i++)
    {
        ans += (mx[X[i]] - 1) * (my[Y[i]] - 1);
    }

    cout << ans << '\n';
}

• Subtask 1: 100 / 100