#include <iostream>
#include <fstream>
using namespace std;
int coridor[256][256],*lumini,n,contor;
int trecutx=1,trecuty=1,ajuns,*bifa,last=1,last2=1;
void read()
{
	int x,y;
	ifstream in("trigame.in");
	in>>n;
	for(int i=1;i<=n;i++)
	{in>>x>>y; coridor[x][y]=coridor[y][x]=1;}
	in.close();
	/*for(int k=1;k<=n;k++){cout<<endl;
	for(int j=1;j<=n;j++)
		cout<<[k][j]<<" ";}*/
}

void reinit()
{   
	delete [] bifa;
	bifa=new int[n+1];
	//cout<<bifa;
    trecutx=1;
	trecuty=1;
	for(int i=1;i<=n;i++)
		{bifa[i]=0;}
		last=1;
		last2=1;
}


void rezolva()
{   int l,x,y,poz_il[256],poz_fat[256];
    bifa=new int[256];
	
	for(int i=1;i<=n;i++)
		{bifa[i]=0;}
	int i,j,k; //Ileana,varf,fat-frumos
	for(i=1;i<=n;i++)  //Fiecare pozitie IL
	 for(k=1;k<=n;k++) //Fiecare pozitie Fat
	 {  if(k!=i)
	 {      //cout<<k<<" "<<i<<endl;
			ajuns=1;
		    poz_il[1]=i;
            poz_fat[1]=k;
			bifa[i]=bifa[k]=1;
last=1;
last2=1;
trecutx=1;
trecuty=1;
		
		  while(ajuns){ajuns=0;
		  l=last;
		 for(x=1;x<=n;x++) 
			if(coridor[x][poz_il[trecutx]]==1&&bifa[x]==0)
            { 
			 poz_il[++last]=x;
			  bifa[x]=1;
			//cout<<poz_il[last]<<" ";
			}
		int l2;
        l2=last2;		
		for(y=1;y<=n;y++) 
			if(coridor[y][poz_fat[trecuty]]==1&&bifa[y]==0)
            { poz_fat[++last2]=y;
			
			  bifa[y]=1;
			  
				ajuns=1;
				
			}
			//cout<<l<<" "<<last<<endl;
		//	cout<<last<<" "<<trecutx<<endl;
			if(l2==last2&&l<last)
            {//   cout<<i<<" "<<k<<endl;
				contor++;}
		trecutx++;
        trecuty++; 		
		}
		 
		reinit();
	 }}		
		
}

int main()
{
	read();
	rezolva();
	ofstream out("trigame.out");
	out<<contor;
	//cout<<endl<<endl<<contor;
    out.close();
	return 0;
}