Submission #1072349

#	Time	Username	Problem	Language	Result	Execution time	Memory
1072349		coolboy19521	Star triangles (IZhO11_triangle)	C++17	100 / 100	482 ms	12252 KiB

triangle

#include "bits/stdc++.h"
#define ll long long

using namespace std;

const int sz = 3e5 + 15;

pair<int,int> ps[sz];

int main() {
    int n;
    cin >> n;

    map<int,int> cx, cy;

    for (int i = 0; i < n; i ++) {
        int x, y;
        cin >> x >> y;

        cx[x] ++, cy[y] ++;
        ps[i] = make_pair(x, y);
    }

    ll r = 0;

    for (int i = 0; i < n; i ++) {
        int x, y;
        tie(x, y) = ps[i];
        cx[x] --, cy[y] --;
        r += cx[x] * cy[y];
        cx[x] ++, cy[y] ++;
    }

    cout << r << '\n';
}

• Subtask 1: 100 / 100