c++ 求星期几?

#include <bits/stdc++.h>
using namespace std;
int main(int argc, char** argv) {
    long long a,b,n=1;
    cin>>a>>b;
    for (int i=0;i<b;i++){
        n=n*a;
        n=n%7;
    }
    if(n==0){
        cout<<"Sunday";
    }else if(n==6){
        cout<<"Saturday";
    }else if(n==5){
        cout<<"Friday";
    }else if(n==4){
        cout<<"Thursday";
    }else if(n==3){
        cout<<"Wednesday";
    }else if(n==2){
        cout<<"Tuesday";
    }else if(n==1){
        cout<<"Monday";
    }
    return 0;
}