极简题解

循环搞定~
不用return 0~

#include<iostream>
using namespace std;
int main(){
    int a,b,sum10=0;
    cin>>a>>b;
    int d=1;
    while(b>0){
        sum10+=(b%10)*d;
        d*=a;
        b/=10;
    }
    cout<<sum10;
}