#include<iostream>

#include<cmath>

using namespace std;

int main()

{

int a,b,n = 0;

cin >> a >> b;

string s;

cin >> s;

string c;

for(int i = 0;i <s.size();i++)

{

if(s[i] >= 'a')

n = n * a+ s[i] - 'a' + 10;

else

n = n * a + s[i] - '0';

}

while(n != 0)

{

if(n % b >= 10)

c = char(n % b - 10 + 'a') + c;

else

c = char(n % b + '0') + c;

n /= b;

}

cout << c;

return 0;

}