#include<stdio.h>
#include<math.h>
int main()
{
   struct student
   {
       int chinese,math,english,s;
   }a[5];
   int cnt=0,n,i,j;
   scanf("%d",&n);
   for(i=1;i<=n;i++)
   {
       scanf("%d%d%d",&a[i].chinese,&a[i].math,&a[i].english);
     a[i].s=a[i].chinese+a[i].math+a[i].english;
   }
   for(i=1;i<=n;i++){
    for(j=i+1;j<=n;j++)
   {
       if(abs(a[i].chinese-a[j].chinese)<=5&&abs(a[i].math-a[j].math)<=5&&abs(a[i].english-a[j].english)<=5&&abs(a[i].s-a[j].s)<=10)
       cnt++;
   }
   }
   printf("%d",cnt);
}