Submission #18635

#	Time	Username	Problem	Language	Result	Execution time	Memory
18635		mindol	Star triangles (IZhO11_triangle)	C++14	100 / 100	203 ms	7036 KiB

triangle

#include<cstdio>
#include<unordered_map>
using namespace std;
unordered_map<int,int> X,Y;
int x[300001],y[300001];
int main()
{
    int n;
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
        scanf("%d %d",&x[i],&y[i]), X[x[i]]++, Y[y[i]]++;
    long long ans=0;
    for(int i=1;i<=n;i++)
        ans+=(X[x[i]]-1ll)*(Y[y[i]]-1);
    printf("%lld",ans);
    return 0;
}

• Subtask 1: 100 / 100