1 #include <stdio.h> 2 #include <string.h> 3 #include <math.h> 4 typedef long long ll; 5  6 int main() 7 { 8     ll n; 9     while( ~scanf( "%I64d", &n ) )10     {11         if( n == 1 )12         {13             puts( "0" );14             continue;15         }16         ll ans = n, cnt;17         for( ll i = 2; i*i <= n; ++i )18             if( n % i == 0 )19             {20                 while( n % i == 0 ) {21                     n /= i;22                     cnt = i;23                 }24             }25         if( n > 1 ) cnt = n;26         printf( "%I64d\n", ans/cnt );27     }28     return 0;29 }