codevs 1497 取余运算

#include <iostream>
#include <cstring>
#include <cstdio>
#define LL long long

using namespace std;

LL b,p,k,i,j;
LL powe(LL m,LL n,LL c)
{
    LL r=1,base=m;
    while(n)
    {
        if(n&1)
            r=r*base%c;
        base=base*base%c;
        n>>=1;
    }
    return r;
}
int main()
{
    ios::sync_with_stdio(false); 
    cin>>b;
    cin>>p;
    cin>>k;
    LL ans=powe(b,p,k);
    cout<<b<<"^"<<p<<" mod "<<k<<"="<<ans;
}