輸入一個數字，在控制檯輸出其對應的月份和該月份對應的天數。

package ch2;
import java.util.*;
public class SwitchOP {

	public static void main(String[] args) {
		System.out.println("請輸入月份：");
		Scanner scanner=new Scanner(System.in);
		int month=scanner.nextInt();
		switch(month){
		case 1: System.out.println("一月有31天");break;
		case 2: System.out.println("二月有28/29天");break;
		case 3: System.out.println("三月有31天");break;
		case 4: System.out.println("四月有30天");break;
		case 5: System.out.println("五月有31天");break;
		case 6: System.out.println("六月有30天");break;
		case 7: System.out.println("七月有31天");break;
		case 8: System.out.println("八月有31天");break;
		case 9: System.out.println("九月有30天");break;
		case 10: System.out.println("十月有31天");break;
		case 11: System.out.println("十一月有30天");break;
		case 12: System.out.println("十二月有31天");break;
		default: System.out.println("無效月份.");
		}
	}

}