WA in FCTRL

[geekakj]

I am getting WA in FCTRL problem.Below is the source code.Please help in pointing out the error.

#include <iostream>
using namespace std;
int main()
{
   long int n = 0;
   long int num = 0;
   long int i=0;
   long int a[100] = {0};
   cin >> num;
   for(;i<num;i++)
      cin>>a[i];
   for(i = 0;i < num;i++)
   {
      n = a[i];
      long int sum = 0;
      while((n/5)!=0)
      {
         sum += n/5;
         n = n/5;
      }
      cout<<sum<<endl;
   }
   return 0;
}