/*
TASK:tri
LANG:C++
*/
#include<iostream>
#include<vector>
using namespace std;
int a[512][512],b[1024][4],n1=0,br=0;
int main()
{
 int n,i,i2,i3,ok,l,i4;
 cin>>n;
 do
 {
  cin>>i>>i2;
  a[i][i2]=1;
  a[i2][i]=1;
 }
 while(i||i2);
 for(i=1;i<=n;i++)
 {
  ok=0;
  for(i2=1;i2<=n;i2++)
  {
   if(a[i][i2])
    for(i3=i+1;i3<=n;i3++)
    {
     if(a[i2][i3])
      if(a[i3][i])
      {
       l=1;
       for(i4=0;i4<n1;i4++)
        if((b[i4][0]==i&&b[i4][1]==i2&&b[i4][2]==i3)||(b[i4][0]==i&&b[i4][1]==i3&&b[i4][2]==i2)||(b[i4][0]==i2&&b[i4][1]==i&&b[i4][2]==i3)||(b[i4][0]==i2&&b[i4][1]==i3&&b[i4][2]==i)||(b[i4][0]==i3&&b[i4][1]==i&&b[i4][2]==i2)||(b[i4][0]==i3&&b[i4][1]==i2&&b[i4][2]==i))
         l=0;
       if(l)
       {
        b[n1][0]=i;
        b[n1][1]=i2;
        b[n1++][2]=i3;
        br++;
        break;
       }
      }
    }
  }
 }
 cout<<br<<endl;
 return 0;
}
