UVA 374 Big Mod

#include<iostream>
#include<cmath>

using namespace std;


int big_mod(int base, int power, int mod)
{
    if(power==0)    return 1;
    else if(power%2==1)
    {
        int p1 = base % mod;
        int p2 = (big_mod(base,power-1,mod))%mod;
        return (p1*p2)%mod;
    }
    else if(power%2==0)
    {
        int p1 = (big_mod(base,power/2,mod))%mod;
        return (p1*p1)%mod;
    }
}

int main()
{
int b,p,m;

while(cin>>b)
{
cin>>p>>m;
int bb;
bb = big_mod(b,p,m);
cout<<bb<<endl;
}

return 0;
}