#include <stdio.h>
#include <stdlib.h>
int chinese[1005],math[1005],eng[1005],all[1005];
int cnt=0;
int main(){
	int n;
	scanf("%d",&n);
	for(int i=1;i<=n;i++){
		scanf("%d%d%d",&chinese[i],&math[i],&eng[i]);
		all[i]=chinese[i]+eng[i]+math[i];
	}
	for(int j=1;j<=n;j++){
		for(int k=j+1;k<=n;k++){
			if( (abs(chinese[j]-chinese[k])<=5) && (abs(math[j]-math[k])<=5 ) && (abs(eng[j]-eng[k])<=5) && (abs(all[j]-all[k]<=10)) ){
				cnt++;
			}
		}
	}
	printf("%d",cnt);
	return 0;
}