Submission #879491

#	Time	Username	Problem	Language	Result	Execution time	Memory
879491		alexdd	Star triangles (IZhO11_triangle)	C++17	100 / 100	239 ms	12300 KiB

triangle

#include<bits/stdc++.h>
using namespace std;
int n;
pair<int,int> v[300005];
map<int,int> frx;
map<int,int> fry;
signed main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        cin>>v[i].first>>v[i].second;
        frx[v[i].first]++;
        fry[v[i].second]++;
    }
    long long cnt=0;
    for(int i=1;i<=n;i++)
    {
        cnt += 1LL*(frx[v[i].first]-1)*(fry[v[i].second]-1);
    }
    cout<<cnt;
    return 0;
}

• Subtask 1: 100 / 100