poj1546

进制转换，java做

StringBuffer 的方法中setCharAt(int,char)可以改变其某位的字符

View Code

import java.io.*;

import java.util.*;

import java.math.*;



public class Main {

    public static void main(String[] args)

    {

        Scanner cin = new Scanner(System.in);

        while (cin.hasNext())

        {

            String st = cin.next();

            int a = cin.nextInt();

            int b = cin.nextInt();

            BigInteger bigA = new BigInteger(st, a);

            StringBuffer ans = new StringBuffer(bigA.toString(b));

            if (ans.length() > 7)

            {

                System.out.println("  ERROR");

                continue;

            }

            for (int i = 0; i < ans.length(); i++)

                if (ans.charAt(i) <= 'z' && ans.charAt(i) >= 'a')

                    ans.setCharAt(i, (char)('A' - 'a' + ans.charAt(i)));

            int len = ans.length();

            for (int i = len; i < 7; i++)

                ans.insert(0,  ' ');

            System.out.println(ans.toString());

        }

    }

}