纯C语言实现万年历
点击打开在线编译器，边学边练
一、项目介绍
需求和功能是用纯C语言实现一个可以属于年份，属于一个年份就可以显示该年各个月份的日历，如同日历一般，每个月当中每天对应的星期均可查看，即万年历，要求格式整齐，星期对照直观。
二、运行截图
启动效果：
输入一个符合条件的年份后：
三、代码思路
首先构思整个需求的思路，即接收一个年份，然后打印该年各个月的日历，其难点在于知道每个月的第一天是星期几，后面的天数即可依次循环打印即可
本项目需要知道的其余几个小技术点和易出错点：
1.判断闰年，这里判断不对易出错，方法是能被4整除并且能被100整除，或者是直接能被400整除。
2.能判断出某月某天是这一年的第几天，方法是把这个月前面的天数+这个月的天数
3.如何知道每个月多少天，这个除了二月其余月是固定的，可以提前写好（二月可以定28天也可以29天），特殊判定这年是否是闰年，来决定是否单独加一天或减一天。
4.格式问题，熟练使用宏定义、switch判断即可，做好实际数字与英文的对应打印
四、完整源码
测试编译器：VC6.0，代码量约近400行，如下：
#include<stdio.h>
#include<windows.h>
#define Mon 1
#define Tues 2
#define Wed 3
#define Thur 4
#define Fri 5
#define Sat 6
#define Sun 0
#define January_days 31
#define February_days 28
#define March_days 31
#define April_days 30
#define May_days 31
#define June_days 30
#define July_days 31
#define August_days 31
#define September_days 30
#define October_days 31
#define November_days 30
#define December_days 31
#define first1month January_days
#define first2month January_days+February_days
#define first3month January_days+February_days+March_days
#define first4month January_days+February_days+March_days+April_days
#define first5month January_days+February_days+March_days+April_days+May_days
#define first6month January_days+February_days+March_days+April_days+May_days+June_days
#define first7month January_days+February_days+March_days+April_days+May_days+June_days \
+July_days
#define first8month January_days+February_days+March_days+April_days+May_days+June_days \
+July_days+August_days
#define first9month January_days+February_days+March_days+April_days+May_days+June_days \
+July_days+August_days+September_days
#define first10month January_days+February_days+March_days+April_days+May_days+June_days \
+July_days+August_days+September_days+October_days
#define first11month January_days+February_days+March_days+April_days+May_days+June_days \
+July_days+August_days+September_days+October_days+November_days
int known_weekday = Tues;
int known_year = 1901;
int konwn_month = 1;
int known_day = 1;
int day_count(int month)
{
switch(month)
{
case 1: return 0;break;
case 2: return first1month;break;
case 3: return first2month;break;
case 4: return first3month;break;
case 5: return first4month;break;
case 6: return first5month;break;
case 7: return first6month;break;
case 8: return first7month;break;
case 9: return first8month;break;
case 10: return first9month;break;
case 11: return first10month;break;
case 12: return first11month;break;
}
}
/*char * month_name(int month)
{
switch(month)
{
case 1:
return "January";
break;
case 2:
return "February";
break;
case 3:
return "March";
break;
case 4:
return "April";
break;
case 5:
return "May";
break;
case 6:
return "June";
break;
case 7:
return "July";
break;
case 8:
return "August";
break;
case 9:
return "September";
break;
case 10:
return "October";
break;
case 11:
return "November";
break;
case 12:
return "December";
break;
default:
break;
}
}*/
char * month_name(int month)
{
switch(month)
{
case 1:
return "一月";
break;
case 2:
return "二月";
break;
case 3:
return "三月";
break;
case 4:
return "四月";
break;
case 5:
return "五月";
break;
case 6:
return "六月";
break;
case 7:
return "七月";
break;
case 8:
return "八月";
break;
case 9:
return "九月";
break;
case 10:
return "十月";
break;
case 11:
return "十一月";
break;
case 12:
return "十二月";
break;
default:
break;
}
}
/*按格式打印某年某月名称*/
void first_line_print(int month, int year)
{
//printf("%20s %d \n",month_name(month),year);
printf("%8d年 %s \n",year, month_name(month));
}
/*按格式打印星期名称*/
void week_print()
{
//printf("%-6s%-6s%-6s%-6s%-6s%-6s%-6s\n","Sun.", "Mon.", "Tues.", "Wed.", "Thur.", "Fri.", "Sat.");
printf("%-3s%-3s%-3s%-3s%-3s%-3s%-3s\n","日", "一", "二", "三", "四", "五", "六");
}
/*计算该年该月份与已知日子之间的距离天数*/
int date_distance_count(int month, int year)
{
int leap_year_count = 0;
int i;
int distance;
if (year > known_year)
{
for (i=known_year; i<year; i++)
{
if(((i%4 == 0) && (i%100 != 0) ) || (i%400 == 0))
{
leap_year_count++;
}
}
if (month > 2)
{
if(((year%4 == 0) && (year%100 != 0) ) || (year%400 == 0))
{
leap_year_count++;
}
}
}
else
if (year == known_year)
{
if (month > 2)
{
leap_year_count = 1;
}
}
distance = (year - known_year)*365 + leap_year_count + day_count(month);
return distance;
}
/*确定该月份第一天是星期几*/
int makesure_firstday_weekday(int month, int year)
{
int date_distance = 0;
int weekday;
date_distance = date_distance_count(month, year);
weekday = (known_weekday + date_distance)%7;
return weekday;
}
/*依次打印出该月份的日子*/
void print_in_turn(int month, int firstday, int year)
{
int i = 1;
int weekday;
switch(firstday)
{
case Sun:
break;
case Mon:
printf("%-3s","");
break;
case Tues:
printf("%-6s","");
break;
case Wed:
printf("%-9s","");
break;
case Thur:
printf("%-12s","");
break;
case Fri:
printf("%-15s","");
break;
case Sat:
printf("%-18s","");
break;
}
switch(month)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
{
for(i=0; i<31; i++)
{
weekday = (firstday + i)%7;
printf("%-3d",i+1);
if(weekday == Sat)
{
printf("\n");
}
}
break;
}
case 2:
{
if(((year%4 == 0) && (year%100 != 0) ) || (year%400 == 0)) /*闰年*/
{
for(i=0; i<29; i++)
{
weekday = (firstday + i)%7;
printf("%-3d",i+1);
if(weekday == Sat)
{
printf("\n");
}
}
break;
}
else /*平年*/
{
for(i=0; i<28; i++)
{
weekday = (firstday + i)%7;
printf("%-3d",i+1);
if(weekday == Sat)
{
printf("\n");
}
}
break;
}
}
case 4:
case 6:
case 9:
case 11:
{
for(i=0; i<30; i++)
{
weekday = (firstday + i)%7;/*计算该天是星期几*/
printf("%-3d",i+1);
if(weekday == Sat)
{
printf("\n");/*如果是星期六，则换行*/
}
}
break;
}
}
}
void date_print(int month, int year)
{
int firstday;
firstday = makesure_firstday_weekday(month, year);
print_in_turn(month, firstday, year);
printf("\n");
}
void main_month(int month, int year)
{
first_line_print(month, year);
week_print();
date_print(month, year);
printf("\n\n");
}
void main_calendar(int year)
{
int i;
for(i=1; i<=12; i++)
{
main_month(i, year);
}
}
int main()
{
int year;
system("title c语言研究中心 www.dotcpp.com");
printf("请输入年份：year = ");
scanf("%d",&year);
printf("\n");
while(year < 1902)
{
printf("请输入大于1901的年份\n");
printf("请输入年份：year = ");
scanf("%d",&year);
printf("\n");
}
main_calendar(year);
scanf(" ");
return 0;
}本文固定URL：https://www.dotcpp.com/course/905
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