Submission #1256469

#	Time	Username	Problem	Language	Result	Execution time	Memory
1256469		raiihan	별들과 삼각형 (IZhO11_triangle)	C++20	100 / 100	485 ms	9212 KiB

triangle

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

signed main() {
	int n;cin>>n;
    map<int,int> x,y;
    vector<pair<int,int>> ps(n);
    for (int i=0;i<n;i++){
        int a,b;cin>>a>>b;
        x[a]++;
        y[b]++;
        ps[i]={a,b};
    }
    int ans=0;
    for (int i=0;i<n;i++){
        ans+=(x[ps[i].first]-1)*(y[ps[i].second]-1);
    }
    cout<<ans;
}

• Subtask 1: 100 / 100