SPOJ:ADDREV

Problem :

http://www.spoj.com/problems/ADDREV/

#include<iostream>
using namespace std;
long long phi(long long n) 
{ 
 long  long result = n; 
        for(long  long i=2;i*i <= n;i++) 
        { 
  if (n%i==0) 
  result-=result/i; 
         while (n%i==0) 
  n/=i; 
        } 
        if (n>1) 
 result-=result/n; 
        return result; 
} 
int main()
{
 long long t,n;
 cin>>t; 
 while(t--)
 {
  cin>>n;
  cout<<phi(n)<<endl;
 }
}