题解 | #单词倒排#

import java.util.*;

// 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 sc = new Scanner(System.in);
        //空格划分输入，保存到数组中
        List<String> list = new ArrayList<>();
        while (sc.hasNext()) {
            String str = sc.next(); //next()遇到空格或者回车就停止
            if(!have2(str)){
                list.add(str);
            }else{
                String[] arr = split2(str);
                for(int j=0; j<arr.length; j++){
                    list.add(arr[j]);
                }
            }
        }

        StringBuilder sb = new StringBuilder();
        Collections.reverse(list);
        for(String sss: list){
            sb.append(sss).append(" ");
        }
        System.out.println(sb.toString());
    }

    public static String[] split2(String s){
        char[] chars = s.toCharArray();
        char temp = ' ';
        for (int i=0; i<chars.length; i++) {
            char c = chars[i];
            if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
                continue;
            } else {
                //c是特殊字符==>间隔符
                s = s.replace(c, temp); //.replace(char oldChar, char newChar)，特别注意要赋值
            }
        }
        return s.split(String.valueOf(temp));
    }

    public static boolean have2(String s){
        char[] chars = s.toCharArray();
        for (char c : chars) {
            if (c<'a' || c>'z' || c<'A' || c>'Z') {
                return true;
            }
        }
        return false;
    }

}