题解 | 句子逆序

import java.util.Scanner;
import java.util.ArrayList;
import java.util.Collections;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        ArrayList<String> list = new ArrayList<>();
        String words[] = s.split(" ");
        for(String word : words){
            list.add(word);
        }
        Collections.reverse(list);
        for(int i = 0;i<list.size();i++){
            if(i==list.size()-1){
                System.out.print(list.get(i));
            }else if(i!= list.size()-1){
                System.out.print(list.get(i)+" ");
            }
        }
    }
}

利用split函数将字符串s分割成若干个小字符串。然后用列表ArrayList，去将每一个小字符串装入list中,由collections.reverse来反转字符串。再for循环将字符串输出