#include <iostream>
#include <string>
using namespace std;

int ctoi(char c){
	if(c>='0' && c<='9') return c-'0';
	else return c - 'A' +10;
}

char itoc(int x){
	if(x<10) return x +'0';
	else return x-10+'a';
}
	
int main(){
	int m,n;
	cin >> m >> n;
	
	string s;
	cin >> s;
	
	long long num=0;
	for(int i=0;i < s.size();i++){
		num = num*m + ctoi(s[i]);
	}
	
	if(num == 0){
		cout << 0;
	}
	
	string ans = "";
	while(num > 0){
		ans = string(1,itoc(num%n)) + ans;
		num /=n;
	}
	cout << ans;
	
	return 0;
}