Java 洛谷 P1425 小鱼的游泳时间

题目链接:https://www.luogu.com.cn/problem/P1425 代码实例：

import java.util.Scanner;

public class Main {
	public static void main(String args[]) {
		Scanner scanner = new Scanner(System.in);
		int a = scanner.nextInt();
		int b = scanner.nextInt();
		int c = scanner.nextInt();
		int d = scanner.nextInt();
		
		int e = c-a;
		int f = d-b;
		if(f