Submission #525278

#	Time	Username	Problem	Language	Result	Execution time	Memory
525278		LucaIlie	Star triangles (IZhO11_triangle)	C++17	100 / 100	296 ms	11772 KiB

triangle

#include <iostream>
#include <unordered_map>

#define MAX_N 300000

using namespace std;

int x[MAX_N], y[MAX_N];
unordered_map <int, int> mpx, mpy;

int main() {
    int n, i;
    long long nrTri;

    cin >> n;
    for ( i = 0; i < n; i++ ) {
        cin >> x[i] >> y[i];
        mpx[x[i]]++;
        mpy[y[i]]++;
    }

    nrTri = 0;
    for ( i = 0; i < n; i++ )
        nrTri += ((long long)mpx[x[i]] - 1) * (mpy[y[i]] - 1);

    cout << nrTri;

    return 0;
}

• Subtask 1: 100 / 100