#include <iostream>
#include <string>
#include <vector>
#include <cmath>

using namespace std;
typedef long long LL;
vector<int> ve;
int main() {
    int a, b;
    string n;
    cin >> a >> n >> b;
    LL res = 0;
    for (int i = 0; i < n.size(); i++) {
        int x;
        if (n[i] >= 'A' && n[i] <= 'Z')
            x = n[i] - 'A' + 10;
        else if (n[i] >= 'a' && n[i] <= 'z')
            x = n[i] - 'a' + 10;
        else 
            x = n[i] - '0';
        res += x * pow(a, n.size() - i - 1); // 十进制
    }
    while (res) {
        int x = res % b;
        if (x >= 10) {
            x = 65 + x - 10;
        } else {
            x = '0' + x;
        }
        ve.push_back(x);
        res /= b;
    }
    for (int i = ve.size() - 1; i >= 0; i--) {
        cout << (char)ve[i];
    }
    cout << endl;
    return 0;
}