题解 | #单词倒排#

import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        String str = in.nextLine();

        char[] cs = str.toCharArray();

        for (int i = 0; i < str.length(); i++) {
            char c = str.charAt(i);
            if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
                cs[i] = c;
            }
            else{
                cs[i] = ' ';
            }
        }

        String tmp = new String(cs);
        String[] str_s = tmp.split("\\s+");
        
        int left = 0;
        int right = str_s.length - 1;
        while(left < right){
            String t = str_s[left];
            str_s[left] = str_s[right];
            str_s[right] = t;
            left++;
            right--;
        }

        System.out.println(String.join(" ",str_s));
    }
}