【练习三】选择结构（if、switch）相关练习

16：使用switch选择结构实现判断某年某月某日是这一年的第几天？

这一题，一定还有更好的方法，只是我没有想到，望大家多加练习

package WorkDemo3;

import java.util.Scanner;

public class DemoText2 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入年份：");
		int year = sc.nextInt();
		
		System.out.println("请输入月份：");
		int month = sc.nextInt();
		System.out.println("请输入日期");
		int day = sc.nextInt();
		
		if(year%4 !=0){
			int x=year;
			switch (month){
			case 1:
				System.out.println(x+"年中第"+day+"天");
				break;
			case 2:
				int number =31+day;
				System.out.println(x+"年中第"+number+"天");
				break;
			case 3:
				int number1 = 31+28+day;
				System.out.println(x+"年中第"+number1+"天");
				break;
			case 4:
				int number2 = 2*31+28+day;
				System.out.println(x+"年中第"+number2+"天");
				break;
			case 5:
				int number3 = 2*31+28+30+day;
				System.out.println(x+"年中第"+number3+"天");
				break;
			case 6:
				int number4 = 3*31+28+30+day;
				System.out.println(x+"年中第"+number4+"天");
				break;
			case 7:
				int number5 = 3*31+28+30*2+day;
				System.out.println(x+"年中第"+number5+"天");
				break;
			case 8:
				int number6 = 4*31+28+30*2+day;
				System.out.println(x+"年中第"+number6+"天");
				break;
			case 9:
				int number7 = 5*31+28+2*30+day;
				System.out.println(x+"年中第"+number7+"天");
				break;
			case 10:
				int number8 = 5*31+28+3*30+day;
				System.out.println(x+"年中第"+number8+"天");
				break;
			case 11:
				int number9 = 6*31+28+3*30+day;
				System.out.println(x+"年中第"+number9+"天");
				break;
			case 12:
				int number10 = 6*31+28+4*30+day;
				System.out.println(x+"年中第"+number10+"天");
				break;
			}
		
		}
		else{
			int y=year;
			switch (month){
			case 1:
				System.out.println(y+"年中第"+day+"天");
				break;
			case 2:
				int number =31+day;
				System.out.println(y+"年中第"+number+"天");
				break;
			case 3:
				int number1 = 31+29+day;
				System.out.println(y+"年中第"+number1+"天");
				break;
			case 4:
				int number2 = 2*31+29+day;
				System.out.println(y+"年中第"+number2+"天");
				break;
			case 5:
				int number3 = 2*31+29+30+day;
				System.out.println(y+"年中第"+number3+"天");
				break;
			case 6:
				int number4 = 3*31+29+30+day;
				System.out.println(y+"年中第"+number4+"天");
				break;
			case 7:
				int number5 = 3*31+29+30*2+day;
				System.out.println(y+"年中第"+number5+"天");
				break;
			case 8:
				int number6 = 4*31+29+30*2+day;
				System.out.println(y+"年中第"+number6+"天");
				break;
			case 9:
				int number7 = 5*31+29+2*30+day;
				System.out.println(y+"年中第"+number7+"天");
				break;
			case 10:
				int number8 = 5*31+29+3*30+day;
				System.out.println(y+"年中第"+number8+"天");
				break;
			case 11:
				int number9 = 6*31+29+3*30+day;
				System.out.println(y+"年中第"+number9+"天");
				break;
			case 12:
				int number10 = 6*31+29+4*30+day;
				System.out.println(y+"年中第"+number10+"天");
				break;
			}
		}
	}
}

17：使用switch选择结构判断一个月份属于一年中的那个季节。（春夏秋冬）

我是根据阳历和平年闰年来做的

package WorkDemo3;

import java.util.Scanner;

public class DemoText1 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入月份：");
        int month = sc.nextInt();
        switch (month){
        case 3:
        case 4:
        case 5:
            System.out.println("这是春天");
            break;
        case 6:
        case 7:
        case 8:
            System.out.println("现在是夏天");
            break;
        case 9:
        case 10:
        case 11:
            System.out.println("秋天就到了");
            break;
            default:
                System.out.println("冬天来了，春天还会远吗");
                break;
        }
    }
}
其中若有错误，望指正。

终于写完了，啊，好累，给个鼓励吧，不要让我求你了