제출 #977066

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
977066		vjudge1	Star triangles (IZhO11_triangle)	C++17	0 / 100	1 ms	6492 KiB

triangle

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

//masukin nilai n; trus masukin nilai Xi dan Yi ke array;;
//cari banyak titik yang Xnya sama dengan Xi; dan Ynya sama dengan Yi, terus kaliin;
//tambahin ke ans;

    const int a=3e5;
    ll x[a + 5], y[a + 5];
    ll cntX[a+5], cntY[a+5];

int main(){
    ll n; cin>>n;
    for(ll i=0; i<n; i++){
        cin>>x[i]>>y[i];
        cntX[x[i]]++;
        cntY[x[i]]++;
    }
    ll ans=0;
    for(ll i=0; i<n; i++){
        ans+=(cntX[x[i]]-1)*(cntY[y[i]]-1);
    }
    cout<<ans<<endl;
}

• Subtask 1: 0 / 100