Submission #4855

#	Time	Username	Problem	Language	Result	Execution time	Memory
4855		cki86201	Star triangles (IZhO11_triangle)	C++98	100 / 100	480 ms	6588 KiB

triangle

#include<stdio.h>
#include<map>
using namespace std;

typedef long long ll;
map <int,int> M[2];
map <int,int>::iterator p;
int x[300030],y[300030];

int main(){
	int n,i;
	scanf("%d",&n);
	for(i=0;i<n;i++){
		scanf("%d%d",x+i,y+i);
		M[0][x[i]]++, M[1][y[i]]++;
	}
	ll ans = 0;
	for(i=0;i<n;i++)ans += (ll)(M[0][x[i]]-1) * (M[1][y[i]]-1);
	printf("%lld",ans);
	return 0;
}

• Subtask 1: 100 / 100