题解 | #HJ030 字符串合并处理#

import java.util.*;

/**
 * HJ30 字符串合并处理
 */
public class HJ030 {

    public static void main(String[] str) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String s1 = sc.next();
            String s2 = sc.next();
            char[] chars = (s1 + s2).toCharArray();
            String[] res = new String[chars.length];
            //偶数位
            char[] r1 = new char[chars.length / 2];
            //奇数位
            char[] r2 = new char[chars.length - chars.length / 2];
            for (int i = 0, j = 0, k = 0; i < chars.length; i++) {
                if (i % 2 == 0) {
                    r2[j] = chars[i];
                    j++;
                } else {
                    r1[k] = chars[i];
                    k++;
                }
            }
            Arrays.sort(r1);
            Arrays.sort(r2);
            for (int i = 0, j = 0, k = 0; i < chars.length; i++) {
                if (i % 2 == 0) {
                    res[i] = getFanyiStr(r2[j]);
                    j++;
                } else {
                    res[i] = getFanyiStr(r1[k]);
                    k++;
                }
            }
            StringBuilder sb = new StringBuilder();
            for (String re : res) {
                sb.append(re);
            }
            System.out.println(sb.toString());
        }
    }

    private static String getFanyiStr(char c) {
        String res;
        if ((c >= '0' && c <= '9')
                || (c >= 'a' && c <= 'f')
                || (c >= 'A' && c <= 'F')) {
            String s = Integer.toBinaryString(Integer.parseInt(Character.toString(c), 16));
            StringBuilder sb = new StringBuilder(s).reverse();
            while (sb.length() < 4) {
                sb.append("0");
            }
            res = Integer.toHexString(Integer.parseInt(sb.toString(), 2)).toUpperCase();
        } else {
            res = Character.toString(c);
        }
        return res;
    }
}