直接分隔取反即可

AC代码：

import java.util.Scanner;

/**

 * @author CC11001100

 */

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		String s = sc.nextLine();

		String[] ss = s.split("\\s+");

		for(int i=ss.length-1; i>=0; i--){

			System.out.print(ss[i] + (i>0 ? " " : ""));

		}

	}

}

题目来源： https://www.nowcoder.com/pat/2/problem/4075

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