#include<cstdio>
#include<cstring>
#include<cmath>
using namespace std;
void trans(char *num, double n); //其他進制轉換成10進制數
int main() {
char num[100];
double n; //n進制數num,字符串類型
while ((cin >> num >> n)) {
trans(num, n);
}
return 0;
}
void trans(char *num, double n) { //n:num的進制 double pow(double jinzhi,int time);
double data = 0;
int len = strlen(num);
for (int i = len - 1; i >= 0; --i) {
data += (num[i] - '0') * pow(n, len - 1 - i);
}
cout << data << endl;
}