Submission #975209

#	Time	Username	Problem	Language	Result	Execution time	Memory
975209		vjudge1	Star triangles (IZhO11_triangle)	C++17	100 / 100	275 ms	12832 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
#define ll long long

const int N = 3e5 + 5;

map < ll, ll > mpx, mpy;

vector < pair < ll, ll >> a ( N );

ll n;

signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0);

    cin >> n;

    for ( int i = 1; i <= n; i++){
        cin >> a[i].first >> a[i].second;
        mpx[a[i].first]++;
        mpy[a[i].second]++;
    }

    ll ans = 0;

    for ( int i = 1; i <= n; i++){
        ans += ( 1ll * ( mpx[a[i].first] - 1 ) * ( mpy[a[i].second] - 1) );
    }

    cout << ans << endl;
}

• Subtask 1: 100 / 100