题目1080：进制转换

import java.util.Scanner;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.FileReader;
import java.math.BigInteger;

class Main {
	private final static boolean DEBUG = false;

	public static void main(String[] args) throws IOException {
		Scanner cin;
		int n, m;
		String s;

		if (DEBUG) {
			cin = new Scanner(new BufferedReader(new FileReader(
					"d:\\OJ\\uva_in.txt")));
		} else {
			cin = new Scanner(new BufferedReader(new InputStreamReader(
					System.in)));
		}

		while (cin.hasNext()) {
			n = cin.nextInt();
			m = cin.nextInt();
			s = cin.next();

			if (s.compareTo("0") == 0) {
				System.out.println(s);
				continue;
			}
			
			BigInteger a = BigInteger.ZERO;
			for (int i = 0; i < s.length(); i++) {
				if (Character.isLetter(s.charAt(i))) {
					a = a.multiply(BigInteger.valueOf(n)).add(
							BigInteger.valueOf(s.charAt(i) - 'A' + 10));
				} else {
					a = a.multiply(BigInteger.valueOf(n)).add(
							BigInteger.valueOf(s.charAt(i) - '0'));
				}
			}

			StringBuffer ans = new StringBuffer();
			BigInteger rem;
			while (a.compareTo(BigInteger.ZERO) != 0) {
				rem = a.remainder(BigInteger.valueOf(m));
				int tmp = Integer.parseInt(rem.toString());
				if (tmp < 10) {
					ans.append((char) ('0' + tmp));
				} else {
					ans.append((char) ('a' + tmp - 10));
				}

				a = a.divide(BigInteger.valueOf(m));
			}

			s = ans.reverse().toString();
			System.out.println(s);
		}
	}
}