日历

思路：求每月第一天是星期几，然后递归

package demo;

import java.util.Scanner;

public class demo {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int sum=0;
        Scanner in=new Scanner(System.in);
        System.out.println("请输入年份:");
        int next_year=in.nextInt();
        System.out.println("请输入月份:");
        int next_month=in.nextInt();
        for(int def_year=1900;def_year