#include<bits/stdc++.h>
using namespace std;
struct person{
	int chinese,math,english,total;
}; 
person a[10000];
int cmp(person a,person b){
	if((abs(a.chinese-b.chinese)<=5&&abs(a.math-b.math)<=5)&&(abs(a.english-b.english)<=5&&abs(a.total-b.total<=10))){
		return 1;
	}
	else return 0;
}
int main(){
	int n,ans=0;
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i].chinese>>a[i].math>>a[i].english;
		a[i].total=a[i].chinese+a[i].math+a[i].english;
	}
	for(int i=1;i<=n;i++){
		for(int j=i+1;j<=n;j++){
			if(cmp(a[i],a[j])==1) ans++;
		}
	}
	cout<<ans;
}