Submission #1219518

#	Time	Username	Problem	Language	Result	Execution time	Memory
1219518		matere	Star triangles (IZhO11_triangle)	C++20	100 / 100	370 ms	9216 KiB

triangle

#include<bits/stdc++.h>
using namespace std;
long long n,a[300005],b[300005];
map<long long,long long>x,y;
int main(){
    cin>>n;
    for(long long i=1;i<=n;i++){
        cin>>a[i]>>b[i];
        x[a[i]]++;
        y[b[i]]++;
    }
    long long ans=0;
    for(long long i=1;i<=n;i++){
        ans+=(x[a[i]]-1)*(y[b[i]]-1);
    }
    cout<<ans<<endl;
}

• Subtask 1: 100 / 100