万年历

/*
  Name: calendar.c version 1.0
  Author: Lynxcn(x-bit)
  Description: 1752.10-9999.12
  Date: 03-31-2004
  Copyright: [email protected]
*/

#include <stdio.h>

int main(void)
{
 int year, month;
 
 int leap(int year);
 int get_days(int year, int month, int date);
 int get_week(int year, int month, int date);
 void calendar(int year, int month);
 
 printf("Enter a year: ");
 scanf("%d", &year);
 while(year<0)
 {
  printf("! illegal year value: year must > 0\n");
  printf("Enter a year: ");
  scanf("%d", &year);
 }
 printf("Enter a month: ");
 scanf("%d", &month);
 while(month<1||month>12)
 {
  printf("! illegal month value: use 1-12\n");
  printf("Enter a month: ");
  scanf("%d", &month);
 }
 calendar(year, month);
 return 0;
}

/*  判断润年  */
int leap(int year)
{
 int leap=0;
 if(year%4==0&&year%100!=0||year%400==0)
  leap=1;
 return(leap);
}
/*  天数  */
int get_days(int year, int month, int date)
{
 int i, days=0;
 int m[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
 if(leap(year))
  m[2]=29;
 for(i=1;i<month;i++)
  days+=m[i];
 days+=date;
 return(days);
}
/*  星期几  */
int get_week(int year, int month, int date)
{
 int week;
 week=(year-1)+(year-1)/4-(year-1)/100+(year-1)/400;
 week+=get_days(year, month, date);
 week%=7;
 return(week);
}
/** calendar  **/
void calendar(int year, int month)
{
 int i, j;
 int m[]={0,31,28,31,30,31,30,31,31,30,31,30,31};
 if(leap(year))
  m[2]=29;
 printf("\n%d.%d", year, month);
 printf("\n***************************\n");
 printf("Sun Mon Tue Wen Thu Fri Sat \n");
 for(j=1; j<=get_week(year, month, 1)*4; j++)
  printf(" ");
 for(i=1;i<=m[month];i++)
 {
  printf("%d",i);
  if(i>=10)
   printf("  ");
  else
   printf("   ");
  if(get_week(year, month, i)==6)
   printf("\n");
 }
 printf("\n***************************\n");
}

本文地址：http://com.8s8s.com/it/it26737.htm