#include<cstdio>
#include<cmath>
using namespace std;
struct score
{
	int ch,ma,en,sum;
};
int main()
{
	int N,num;
	scanf("%d",&N);
	score a[N];
	for(int i=0;i<=N-1;i++)
	{
		scanf("%d",&a[i].ch);
		scanf("%d",&a[i].ma);
		scanf("%d",&a[i].en);
		a[i].sum=a[i].ch+a[i].ma+a[i].en;
	}
	for(int i=0;i<=N-1;i++)
	{
		for(int j=i+1;j<=N-1;j++)
		{
			if(abs(a[i].ch-a[j].ch)<=5)num++;
			if(abs(a[i].ma-a[j].ma)<=5)num++;
			if(abs(a[i].en-a[j].en)<=5)num++;
			if(abs(a[i].sum-a[j].sum)<=10)num++;
		}
	}
	int people=num/4;
	printf("%d",people);
	return 0;}