1 /*************************************************************************
 2     > File Name: code/bc/#50/1002.cpp
 3     > Author: 111qqz
 4     > Email: rkz2013@126.com 
 5     > Created Time: 2015年08月08日 星期六 20时31分14秒
 6  ************************************************************************/
 7 
 8 #include<iostream>
 9 #include<iomanip>
10 #include<cstdio>
11 #include<algorithm>
12 #include<cmath>
13 #include<cstring>
14 #include<string>
15 #include<map>
16 #include<set>
17 #include<queue>
18 #include<vector>
19 #include<stack>
20 #define y0 abc111qqz
21 #define y1 hust111qqz
22 #define yn hez111qqz
23 #define j1 cute111qqz
24 #define tm crazy111qqz
25 #define lr dying111qqz
26 using namespace std;
27 #define REP(i, n) for (int i=0;i<int(n);++i)  
28 typedef long long LL;
29 typedef unsigned long long ULL;
30 const int inf = 0x7fffffff;
31 bool v[10][10];
32 int n;
33 int x[30],y[30];
34 
35 int dis( int x1,int y1,int x2,int y2)
36 {
37     int res ;
38     res = (x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
39     return res;
40 }
41 int main()
42 {
43     while (scanf("%d",&n)!=EOF)
44     {
45     int ans = 0;
46     memset(v,false,sizeof(v));
47     for ( int i = 0 ;  i < n ; i++ )
48     {
49         scanf("%d%d",&x[i],&y[i]);
50     }
51     for ( int i = 0  ; i < n ; i++ )
52     {
53         for (int j = i+1 ; j < n ; j ++)
54         {
55         for ( int k =  j + 1 ; k < n ; k ++)
56         {
57             for ( int l = k + 1 ; l < n ; l++)
58             {
59             int d[10];
60             d[0]=dis(x[i],y[i],x[j],y[j]);
61             d[1]=dis(x[i],y[i],x[k],y[k]);
62             d[2]=dis(x[i],y[i],x[l],y[l]);
63             d[3]=dis(x[j],y[j],x[k],y[k]);
64             d[4]=dis(x[j],y[j],x[l],y[l]);
65             d[5]=dis(x[k],y[k],x[l],y[l]);
66             sort(d,d+6);
67             if (d[0]==d[1]&&d[2]==d[3]&&d[0]==d[2]&&d[4]==d[5]&&d[4]==2*d[0])
68             {
69                 ans++;
70             }
71             }
72         }
73         }
74     }
75     cout<<ans<<endl;
76 
77     }
78     return 0;
79 }