#include<stdio.h>
int abs(int x)
{
    if (x<0)
    x=-x;
    return x;
}
int main()
{
    int N,c[1005],m[1005],e[1005],s[1005],cnt=0;
    scanf("%d",&N);
    for(int i=1;i<=N;++i)
    {
        scanf("%d%d%d",&c[i],&m[i],&e[i]);
        s[i]=c[i]+m[i]+e[i];
    }
    for(int i=1;i<=N;i++)
    {
        for(int j=i+1;j<=N;j++)
        {
            if((abs(c[i]-c[j]<=5))&&(abs(m[i]-m[j]<=5))&&(abs(e[i]-e[j]<=5))&&(abs(s[i]-s[j]<=10)))
            {
                cnt++;
            }
        }
    }
    printf("%d",cnt);
    return 0;
}