#include <bits/stdc++.h>

 using namespace std;

 typedef long long ll;

 int a[];

 int main()

 {

     int n;

     while (cin >> n)

     {

         ll ans = ;

         for (int i = ; i < n; i++) { cin >> a[i]; a[i] = abs(a[i]); }

         sort(a, a + n);

         for (int i = ; i < n; i++)

         {

             ans += upper_bound(a + i + , a + n,  * a[i]) - a - i - ;

         }

         cout << ans << endl;

     }

     return ;

 }

 #include <bits/stdc++.h>

 using namespace std;

 typedef long long ll;

 int a[];

 int main()

 {

     int n;

     while (cin >> n)

     {

         ll ans = ;

         for (int i = ; i < n; i++) { cin >> a[i]; a[i] = abs(a[i]); }

         sort(a, a + n);

         int l = , r = ;

         while (l < n)

         {

             while (r < n && a[r] <=  * a[l]) r++;

             ans += r - l - ;

             l++;

         }

         cout << ans << endl;

     }

     return ;

 }