#include<stdio.h>

#include<math.h>

typedef struct student{

int a;

int b;

int c;

}STU;

int main(){

int n;

scanf("%d",&n);

STU ai[n];

for(int i=0;i<n;i++){

scanf("%d %d %d",&ai[i].a,&ai[i].b,&ai[i].c); }

int find = 0;

for(int i=0;i<n;i++){

for(int k=i+1;k<n;k++){

int sum = (ai[i].a+ai[i].b+ai[i].c)- (ai[k].a+ai[k].b+ai[k].c);

if(abs(ai[i].a-ai[k].a)<=5&&abs(ai[i].b-ai[k].b)<=5&&abs(ai[i].c-ai[k].c)<=5&&abs(sum)<=10) {

find++;

}

}

}

printf("%d",find);

return 0;

}