#include<stdio.h>
#include<math.h>
#include<stdlib.h>
int main(void)
{
int CHINESE[150],MATH[150],ENGLISH[150],number,all[150];
scanf("%d\n",&number);
for(int i = 0;i<number;i++){
scanf("%d %d %d",&CHINESE[i],&MATH[i],&ENGLISH[i]);
all[i] = CHINESE[i]+MATH[i]+ENGLISH[i];
}
int couple = 0;
for(int i = 0;i<number;i++){
for(int j = i+1;j<number;j++){
if(abs(CHINESE[i]-CHINESE[j])<=5&&
abs(MATH[i]-MATH[j])<=5&&
abs(ENGLISH[i]-ENGLISH[j])<=5&&
abs(all[i]-all[j])<=10){
couple++;
}
}
printf("%d\n",couple);
}
return 0;
}