#include<bits/stdc++.h>
using namespace std;
struct student
{
    double x;
	double y;
	double z;	
};
int main()
{
	struct student arr[10086];
	int n=0;
	int N;
	cin>>N;
	for(int i=0;i<N;i++)
	{
		cin>>arr[i].x>>arr[i].y>>arr[i].z;
	}
	for(int i=0;i<N;i++)
	{
		for(int j=i+1;j<N;j++)
		{
			if(fabs(arr[i].x-arr[j].x)<=5&&(arr[i].y-arr[j].y)<=5&&(arr[i].z-arr[j].z)<=5&&fabs((arr[i].x+arr[i].y+arr[i].z)-(arr[j].x+arr[j].y+arr[j].z)<=10))
			{
				n++;
			}
		}
	}
	cout<<n<<endl;
	return 0;
}