875. 快速幂

Posted 2021-05-23 幽殇默

https://www.acwing.com/problem/content/description/877/
模板一：

#include<cstdio>
#include<iostream>
#define ll long long int
using namespace std;
int quick_pow(ll a,ll b,ll c)
{
    int sum=1;
    while(b)
    {
        if(b&1) sum=sum*a%c;
        b=b>>1;
        a=(a*a)%c;
    }
    return sum;
}
int main(void)
{
    int n; cin>>n;
    while(n--)
    {
        ll a,b,c; cin>>a>>b>>c;
        cout<<quick_pow(a,b,c)<<endl;
    }
    return 0;
}

模板二:

#include<cstdio>
#include<iostream>
#define ll long long int
using namespace std;
ll quick_pow(ll a,ll b,ll c)
{
    if(b==0) return 1;
    if(b&1) return a*quick_pow(a,b-1,c)%c;
    else 
    {
        ll t=quick_pow(a,b/2,c)%c;
        return (t*t)%c;
    }
}
int main(void)
{
    int n; cin>>n;
    while(n--)
    {
        ll a,b,c; cin>>a>>b>>c;
        cout<<quick_pow(a,b,c)<<endl;
    }
    return 0;
}