AcWing每日一题--a^b

https://www.acwing.com/problem/content/91/

考察快速幂的知识；

#include<iostream>
using namespace std;
typedef long long LL;
LL ksm(LL a,LL b,LL p){
    LL res=1;
    while(b){
        if(b&1){
            res=(res*a)%p;
        }
        a=a*a%p;
        b>>=1;
    }
    return res%p;
}
int main(void){
    LL a,b,p;
    cin>>a>>b>>p;
    cout<<ksm(a,b,p);
    return 0;
}