题解 | #单词倒排#

import java.util.*;

public class Main {
    public static void main(String[] args) {
        //从控制台获取数据
        Scanner in = new Scanner(System.in);
        String s = in.nextLine();
        //将非构成单词的字符改为单词间隔符
        int length = s.length();
        for (int i = 0; i < length; i++) {
            String s1 = String.valueOf(s.charAt(i));
            if (!s1.matches("^[A-Z]|[a-z]$")) {
                s = replaceAtIndex(i, s, " ");
            }
        }
        String[] s1 = s.split(" ");
        //倒序输出字符
        StringBuffer stringBuffer = new StringBuffer();
        for (int i = 0; i < s1.length; i++) {
            String s2 = s1[s1.length - 1 - i];
            stringBuffer.append(s2 + " ");
        }
        System.out.println(stringBuffer);
    }

    private static String replaceAtIndex(int i, String oldStr, String newStr) {
        return oldStr.substring(0, i) + newStr + oldStr.substring(i + 1);
    }
}

解题思路:

1, 将非构成单词的字符改为单词间隔符;

2, 将字符串转化为数组;

3, 倒序遍历数组并进行输出即可