打印日历

输入年份，月份，打印出该月日历表。

：日历表从2000年起始。

package repeat_job1;

public class Calendar {
	public Calendar(){}
	private int []a={366,365,365,365};
	public int number_Days(int m,int n)
	{
		int num1=((m-2000)/4)*1461;
		int num2=0,sum_days=0;
		for(int i=0;i<(m-2000)%4;i++)
		{
			num2+=a[i];
		}
		sum_days=num1+num2+number_Day(m,n);
		return sum_days;
	}
	public int leapyear(int m)
	{
		if((m%4==0&&m%100!=0)||m%400==0)
		{
			return 29;
		}
		else 
		{
			return 28;
		}
	}
	public int number_Day(int m,int n)
	{
		int r=0;
		switch(n)
		{
		case 12:r+=30;
		case 11:r+=31;
		case 10:r+=30;
		case 9:r+=31;
		case 8:r+=31;
		case 7:r+=30;
		case 6:r+=31;
		case 5:r+=30;
		case 4:r+=31;
		case 3:r+=leapyear(m);
		case 2:r+=31;
		case 1:r+=0;
		}
		return r;
	}
	public void print(int m,int n)
	{
		System.out.println("星期日"+"\t"+"星期一"+"\t"+"星期二"+"\t"+"星期三"+"\t"+"星期四"+"\t"+"星期五"+"\t"+"星期六");
		int mod,day;
		mod=(1+number_Days(m,n))%7;//为什么加1？
		switch(mod)
		{
		case 2:System.out.print("");break;
		case 3:System.out.print("");break;
		case 4:System.out.print("\t");break;
		case 5:System.out.print("\t\t");break;
		case 6:System.out.print("\t\t\t");break;
		case 0:System.out.print("\t\t\t\t");break;
		case 1:System.out.print("\t\t\t\t\t");break;
		}
		if(n==1||n==3||n==5||n==7||n==8||n==10||n==12)
		{
			
			for(day=1;day<=31;day++)
			{
				mod=(number_Days(m,n)+day)%7;
				switch(mod)
				{
				case 2:System.out.print(" "+day);break;
				case 3:System.out.print("\t"+day);break;
				case 4:System.out.print("\t"+day);break;
				case 5:System.out.print("\t"+day);break;
				case 6:System.out.print("\t"+day);break;
				case 0:System.out.print("\t"+day);break;
				case 1:System.out.println("\t"+day);break;
		
				}
			}
		}
		else if(n==2)
		{
			for(day=1;day<=leapyear(m);day++)
			{
					mod=(number_Days(m,n)+day)%7;
					switch(mod)
					{
					case 2:System.out.print(" "+day);break;
					case 3:System.out.print("\t"+day);break;
					case 4:System.out.print("\t"+day);break;
					case 5:System.out.print("\t"+day);break;
					case 6:System.out.print("\t"+day);break;
					case 0:System.out.print("\t"+day);break;
					case 1:System.out.println("\t"+day);break;
					}
				}
			}
			else{
				for(day=1;day<=30;day++)
				{	
					mod=(number_Days(m,n)+day)%7;
					switch(mod)
					{
					case 2:System.out.print(" "+day);break;
					case 3:System.out.print("\t"+day);break;
					case 4:System.out.print("\t"+day);break;
					case 5:System.out.print("\t"+day);break;
					case 6:System.out.print("\t"+day);break;
					case 0:System.out.print("\t"+day);break;
					case 1:System.out.println("\t"+day);break;
					}
				}
			}
	}
}

　　

import repeat_job1.Calendar;
import java.util.Scanner;
public class Test2 {
    public static void main(String[] args)
    {
        Calendar ca=new Calendar();
        Scanner reader=new Scanner(System.in);
        System.out.println("请输入年份：");
        int m=reader.nextInt();
        System.out.println("请输入月份：");
        int n=reader.nextInt();
        reader.close();
        ca.print(m,n);
        
    }

}