Submission #1291447

#	Time	Username	Problem	Language	Result	Execution time	Memory
1291447		haha	Star triangles (IZhO11_triangle)	C++20	100 / 100	144 ms	6548 KiB

triangle

#include <bits/stdc++.h>
#define ll long long
#define f first
#define s second
using namespace std;
const int maxn=1e6+5;

int n;
int x[maxn],y[maxn],row[maxn],col[maxn];
vector<int> nen;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);cout.tie(0);
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>x[i]>>y[i];
        nen.push_back(x[i]);
        nen.push_back(y[i]);
    }
    sort(nen.begin(),nen.end());
    nen.erase(unique(nen.begin(),nen.end()),nen.end());
    int maxX=0,maxY=0;
    for(int i=1;i<=n;i++){
        x[i]=lower_bound(nen.begin(),nen.end(),x[i])-nen.begin()+1;
        y[i]=lower_bound(nen.begin(),nen.end(),y[i])-nen.begin()+1;
        row[x[i]]++;
        col[y[i]]++;
    }
    ll ans=0;
    for(int i=1;i<=n;i++){
        ans+=(row[x[i]]-1)*(col[y[i]]-1);
    }
    cout<<ans;

}

• Subtask 1: 100 / 100