题解 | #字符逆序#

• HJ31 单词倒排基础上修改即可
• 思路注释在代码

import java.io.*;
import java.util.Stack;


public class Main {

    public static void main(String[] args) throws IOException {
//        String str = "$bo*y gi!r#l";
        BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in));
        String str = bufferedReader.readLine();
        char[] chars = str.toCharArray();
        StringBuilder stringBuilder = new StringBuilder();
        Stack<String> stack = new Stack();
        /**
         * 字符串转数组遍历
         */
        for (int i = 0; i < chars.length; i++) {
            /**
             * 若是字符则保存
             */
            if (Character.isLetter(chars[i]) && i <= chars.length - 1) {
                stringBuilder.append(chars[i]);
            }
            /**
             * 若不是字符则添加之前保存的字符串，并添加该字符
             */
            else if (!Character.isLetter(chars[i]) && stringBuilder.length() != 0) {
                stack.push(mothod(stringBuilder.toString()));
                stack.push(String.valueOf(chars[i]));
                stringBuilder = new StringBuilder();
            }
            /**
             * 若不是字符且无缓存的字符串，则添加该字符
             */
            else if (!Character.isLetter(chars[i]) && stringBuilder.length() == 0) {
                stack.push(String.valueOf(chars[i]));
            }
            /**
             * 单独添加最后的
             */
            if (i == chars.length - 1 && stringBuilder.length() != 0) {
                stack.push(mothod(stringBuilder.toString()));
            }
        }
        /**
         * 逆序输出
         */
        while (!stack.isEmpty()) {
            if (stack.size() != 1) {
                System.out.print(stack.pop());
            } else {
                System.out.print(stack.pop());
            }
        }
    }

    /**
     * 翻转字符串
     * @param str
     * @return
     */
    public static String mothod(String str) {
        StringBuilder stringBuilder = new StringBuilder();
        char[] chars = str.toCharArray();
        for (int i = chars.length - 1; i >= 0; i--) {
            stringBuilder.append(chars[i]);
        }
        return stringBuilder.toString();
    }