#include <fstream> 
#include <algorithm> 
#include <cmath> 
using namespace std; 
 
 
int n,nrt; 
struct P{double x,y;}a[1503]; 
 
 
double dist(P x,P y) 
{ 
    
return (x.x-y.x)*(x.x-y.x)+(x.y-y.y)*(x.y-y.y); 
} 
 
 
bool equal(double x,double y) 
{ 
    
if (fabs(x-y)>1e-3)return 0; 
    
return 1; 
} 
 
 
bool compare(P t, P yt) 
{ 
    
return t.x>yt.x; 
} 
 
 
int main() 
{ 
    
int i,j,k; 
    
ifstream in("triang.in"); 
    
in>>n; 
    
for(i=0;i<n;i++) 
        
in>>a[i].x>>a[i].y; 
    
in.close(); 
    
sort(a,a+n,compare); 
    
for(i=0;i<n;i++) 
        
for(j=i+1;j<n;j++) 
            
for(k=j+1;k<n;k++) 
                
if(equal(dist(a[i],a[j]),dist(a[j],a[k]))&&equal(dist(a[j],a[k]),dist(a[k],a[i])) ) 
                
{ 
                    
nrt++; 
                    
break; 
                
} 
    
ofstream("triang.out")<<nrt<<'\n'; 
    
return 0; 
}