10
-2 1
2 -2
-1 -2
0 0
2 -1
0 -2
2 2
0 2
-1 -1
1 -2
 40
-8 24
2 -1
1 -18
72 -70
5 -4
-308 436
-19 40
36 -35
-178 265
-1 2
-7 30
-1 0
3 -2
200 -285
17 -16
-35 74
0 -4
-86 106
-1 4
-7 6
0 1
-5 4
-2 3
6 -5
-4 5
181 -262
76 -118
0 0
-7 18
-58 104
-5 6
-6 12
-3 4
1 0
11 -10
-86 130
-3 6
153 -236
-183 270
-33 64
 5
0 -1
0 -2
0 -3
0 -4
0 -5
 10
0 1
-1 -1
1 1
-1 0
1 -1
-2 -1
-2 2
-2 0
0 -2
0 -1
 20
-1 18
-2 5
-5 4
2 -33
9 -18
0 0
11 -22
2 0
-1 2
-4 41
1 6
1 -2
6 -12
0 1
-3 6
3 -6
3 -8
-1 4
2 -5
1 0
 10
2 1
-1 0
-2 -1
-1 1
0 2
2 -2
0 0
-2 -2
0 -2
-2 1
 20
-3 -3
0 4
-3 1
1 1
-1 2
-4 4
3 -1
-3 0
0 2
4 0
2 3
2 4
4 -3
-4 3
-1 1
1 3
-2 4
1 -2
1 -1
3 0
 3
0 0
0 -1
0 1
 10
2 1
-1 1
0 0
-3 1
-2 -3
-1 -2
-1 -1
1 2
3 -2
0 -2
 3
3 3
1 2
1 1
 4
0 0
1 0
2 0
3 0
 9
1 1
1 0
0 1
0 0
-1 0
-1 1
-1 -1
1 -1
0 -1
 7
1 1
-1 -1
1 0
0 1
-1 0
0 -1
0 0

4
 57
 4
 5
 21
 4
 10
 1
 1
 0
 2
 8
 3

#include <bits/stdc++.h>
using namespace std;
const int maxint = -1u >> 1;
template <class T>
bool get_max(T& a, const T& b) {
  return b > a ? a = b, 1 : 0;
}
template <class T>
bool get_min(T& a, const T& b) {
  return b < a ? a = b, 1 : 0;
}
typedef struct path {
  double a;
  double b;
  double d;
} path;
path pa[4500000];
int n;
struct node {
  double x;
  double y;
} p[3000];
int comp(path l, path r) {
  return l.d != r.d ? l.d < r.d : (l.a != r.a ? l.a < r.a : l.b < r.b);
}
int main() {
  int i, j, k = -1, cnt = 0;
  cin >> n;
  for (i = 0; i < n; i++) cin >> p[i].x >> p[i].y;
  for (i = 0; i < n; i++)
    for (j = i + 1; j < n; j++) {
      pa[++k].d = sqrt((p[i].x - p[j].x) * (p[i].x - p[j].x) +
                       (p[i].y - p[j].y) * (p[i].y - p[j].y));
      pa[k].a = i;
      pa[k].b = j;
    }
  k += 1;
  sort(pa, pa + k, comp);
  for (i = 0; i < k; i++)
    for (j = i + 1; j < k; j++) {
      if (pa[i].a != pa[j].a && pa[i].a != pa[j].b && pa[i].b != pa[j].a &&
          pa[i].b != pa[j].b)
        continue;
      double a0, b0, c0;
      if (pa[i].a == pa[j].a) {
        a0 = pa[i].a;
        b0 = pa[i].b;
        c0 = pa[j].b;
      }
      if (pa[i].b == pa[j].b) {
        a0 = pa[i].b;
        b0 = pa[i].a;
        c0 = pa[j].a;
      }
      if (pa[i].a == pa[j].b) {
        a0 = pa[i].a;
        b0 = pa[i].b;
        c0 = pa[j].a;
      }
      if (pa[i].b == pa[j].a) {
        a0 = pa[i].b;
        b0 = pa[i].a;
        c0 = pa[j].b;
      }
      double sum = pa[i].d + pa[j].d;
      double g = min(b0, c0), u = max(b0, c0);
      int l = j + 1, r = k - 1, mid;
      while (l <= r) {
        if (l == r) {
          if (pa[l].d == sum)
            if ((pa[l].a == b0 && pa[l].b == c0) ||
                (pa[l].b == b0 && pa[l].a == c0))
              cnt++;
          break;
        }
        mid = (l + r) / 2;
        if (pa[mid].d < sum)
          l = mid + 1;
        else if (pa[mid].d == sum) {
          if (pa[mid].a > g)
            r = mid - 1;
          else if (pa[mid].a == g) {
            if (pa[mid].b > u)
              r = mid - 1;
            else if (pa[mid].b == u) {
              cnt++;
              break;
            } else
              l = mid + 1;
          } else
            l = mid + 1;
        } else
          r = mid - 1;
      }
    }
  cout << cnt << endl;
  return 0;
}
