#include<stdio.h>
#include<stdlib.h>
int runYear(int n);    //日历不会写痛苦 
int RunYear(int year);
void printMonth(int year, int month);
int dayOfWeek(int year, int month, int day);
void printMonth(int year, int month) 
{
    int daysInMonth[] = {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
    int startDay = dayOfWeek(year, month, 1);
    int days = daysInMonth[month - 1];
    if (month == 2 && RunYear(year)) 
	{
        days = 29;
    } 
	else if (year == 1582 && month == 10) 
	{
        days = 21;                        
    }

    printf("\n%d年%d月\n", year, month);
    printf("日 一 二 三 四 五 六\n");

    // 打印空格直到第一天
    for (int i = 0; i < startDay; i++) 
	{
        printf(" ");
    }

    // 打印日期
    for (int day = 1; day <= days; day++) 
	{
        printf("%2d ", day);
        if ((day + startDay) % 7 == 0) 
		{
            printf("\n");
        }
    }
    printf("\n");
}

int dayOfWeek(int year, int month, int day) 
{
    if (month < 3) 
	{
        month += 12;
        year -= 1;
    }
    int k = year % 100;
    int j = year / 100;
    int h = day + 13 * (month + 1) / 5 + k + k / 4 + j / 4 + 5 * j;      //zeller公式
    h = h % 7;
    return 0;
}
int RunYear(int year) 
{
    return (year % 4 == 0 && year % 100 != 0) || (year % 400 == 0);
}
int runYear(int n)
{
	printf("请输入年份\n");
	scanf("%d",&n);
	if(n%4==0&&n%100!=0||n%400==0)
	{
		printf("是闰年\n");
	}
	else
	{
		printf("不是闰年\n");
	}
}

int main()
{
	int choice,n,year,month,day;
	printf("1.查询对应的年份的日历\n");
	printf("2.查询对应日期的星期\n");
	printf("3.查询对应年份是否为闰年\n");
	printf("4.退出\n");
	printf("请选择序号="); 
	scanf("%d",&choice);
	do
	{
		switch(choice)
		{
			case 1:
				{
					int year;
                    printf("请输入年份：");
                    scanf("%d", &year);

                    // 打印全年的日历
                    for (int month = 1; month <= 12; month++) 
					{
                    printMonth(year, month);
                    }
                    return 0;
				}
			case 2:
				{
	                printf("请输日期（年 月 日）\n");  
	                scanf("%d %d %d",&year,&month,&day);
	                int runYear(year);
	                if(0)
	                {
		                if (month < 3)    //平年 
		                {
                            month += 12;
                            year -= 1;
                        }
                        int c = year % 100;
                        int y = year / 100;
                        int h = day + 13 * (month + 1) / 5 + c + c / 4 + y / 4 + 5 * y;  //zeller公式 
                        h = h % 7;
                        printf("星期%d",h);
	                }
	                else
	                {
		                if (month < 3)    //润年 
		                {
                            month += 12;
                            year -= 1;
                        }
                        int c = year % 100;
                        int y = year / 100;
                        int h = day-1 + 13 * (month + 1) / 5 + c + c / 4 + y / 4 + 5 * y;  //zeller公式 
                        h = h % 7;
                        printf("星期%d",h);
	                }
	                return 0;
				}
			case 3:
				{
					runYear(n);
				}
			case 4:
				    return 0;
			default:
				{
			        printf("输入错误！请重新选择\n");
			        printf("请选择序号=");
			        scanf("%d",&choice);
			    }
		}
	} while(choice);
	 return 0;
}