#include<stdio.h>
#include<stdlib.h>
int main()
{
	int n,i,j,k,s=0,h=1,flag=0,y;
	int c[1001] = {};
	int m[1001] = {};
	int e[1001] = {};
	int sum1[1001] = {};
	int sum;
	scanf("%d",&n);
	for (int x = 0; x < n; x++)
	{
		scanf("%d%d%d",&i,&j,&k);
		c[x] = i;
		m[x] = j;
		e[x] = k;
	}

	for (int x = 0; x < n; x++)//控制首元素
	{
		for (y = h; y <=n; y++)//控制后面元素
		{
			h++;
			sum1[x]= c[x]+m[x]+e[x];
			sum1[y] = c[y] + m[y] + e[y];
			sum = abs(sum1[x] - sum1[y]);
			if(abs(c[x] - c[y])<= 5&&abs(m[x] - m[y]) <= 5&& abs(e[x] - e[y]) <= 5);
			flag = 1;
			if (flag&&sum <= 10)
				s++;
		}
	}
	printf("%d",s);
	return 0;
}