题解 | #字符串合并处理#

//这题的测试用例有坑
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        while (sc.hasNext()) {
            String str1 = sc.next();
            String str2 = sc.next();
            StringBuilder sb = new StringBuilder(str1 + str2);
            List<Character> listJ = new ArrayList<>();
            List<Character> listO = new ArrayList<>();
            for (int i = 0; i < sb.length(); i++) {
                if (i % 2 == 0) {
                    listO.add(sb.charAt(i));
                } else {
                    listJ.add(sb.charAt(i));
                }
            }
            Collections.sort(listJ);
            Collections.sort(listO);
            StringBuilder sb1 = new StringBuilder();
            for (int i = 0, j = 0; i < sb.length(); i++) {
                if (i % 2 == 0) {
                    sb1.append(listO.get(j));
                } else {
                    sb1.append(listJ.get(j));
                }
                if (i % 2 != 0) {
                    j++;
                } else {
                    continue;
                }
            }
            String string = getRes(sb1.toString());
            System.out.println(string);
        }
    }

    private static String getRes(String s) {
        char[] chars = s.toCharArray();
        StringBuilder stringBuilder = new StringBuilder();
        for (int i = 0; i < chars.length; i++) {
            if (Character.isDigit(chars[i])) {
                StringBuilder sb = new StringBuilder(Integer.toBinaryString(chars[i] - '0'));
                sb.reverse();
                while (sb.length() < 4) {
                    sb.append("0");
                }
                int i1 = Integer.parseInt(sb.toString(), 2);
                String string = Integer.toHexString(i1);
                stringBuilder.append(string.toUpperCase());
            } else if (Character.isLetter(chars[i]) && Character.toUpperCase(chars[i]) >= 'A' && Character.toUpperCase(chars[i]) <= 'F') {
                StringBuilder sb = new StringBuilder(Integer.toBinaryString(Integer.parseInt(String.valueOf(chars[i]), 16)));
                sb.reverse();
                if (sb.length() < 4) {
                    sb.append("0");
                }
                int i1 = Integer.parseInt(sb.toString(), 2);
                String string = Integer.toHexString(i1);
                stringBuilder.append(string.toUpperCase());
            }else {
                stringBuilder.append(chars[i]);
            }
        }
        return stringBuilder.toString();
    }
}