Submission #4874

#	Time	Username	Problem	Language	Result	Execution time	Memory
4874		ainta	Star triangles (IZhO11_triangle)	C++98	100 / 100	476 ms	6588 KiB

triangle

#include<stdio.h>
#include<algorithm>
#include<map>
using namespace std;
map<int, int>Map1, Map2;
int n, w[300010][2], i;
long long R;
int main()
{
	scanf("%d", &n);
	for (i = 0; i < n; i++){
		scanf("%d%d", &w[i][0], &w[i][1]);
		Map1[w[i][0]]++, Map2[w[i][1]]++;
	}
	for (i = 0; i < n; i++){
		R = R +(long long)(Map1[w[i][0]] - 1)*(Map2[w[i][1]] - 1);
	}
	printf("%lld\n", R);
}

• Subtask 1: 100 / 100