baza b to baza 10

#include<iostream>
using namespace std;
int main()
{
    int x10=0, xb, b, pb=1;
    cin>>xb>>b;
    while(xb)
    {
        int cifra=xb%10;
        x10=x10+cifra*pb;
        pb*=b;
        xb=xb/10;
    }
    cout<<x10;
    return 0;
}