题解 | #句子逆序#

import java.util.Scanner;
import java.util.Stack;
// 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 scanner = new Scanner(System.in);
        String str = scanner.nextLine();
        Stack<Character> stack = new Stack<>();
        int j = 0;
        for(int i = str.length()-1;i>=0;i--){
            if(str.charAt(i)!=' '){
                stack.push(str.charAt(i));
                j++;
            }else{
                if(stack.empty()) continue;
                for(int a=0;a<j;a++){
                    System.out.print(stack.peek());
                    stack.pop();
                }
                System.out.print(" ");
                j = 0;
            }
        }
        for(int a=0;a<j;a++){
                    System.out.print(stack.peek());
                    stack.pop();
                }
    }
}