注意：下面的程序需要以命令行的格式运行，例如，把编绎好的可执行文件的名字为 filename，那要查看某2002/01/01就输入 filename 2002/02/01，要查看2002年1月份就输入filename 2002/01或filename2002/01/0。
/*** 万年历 ***/
/*** 命令行:
若查看某一天,例如 calen 2001/12/28
若查看某个月,例如 calen 2001/12/0 或 calen 2001/12
***/
/**************************************************
1. 以2000/01/01日为星期六为基准。
2. dy为该年 1月1号 到2000年1月1号的 " 星期差 "
3. dm为该月以前的月所引起的 " 星期差 "
4. m2为二月所引起的 " 星期差 "
**************************************************/
main(int x,char **date)
{
int year=0,month=0,day=0,week;
int d,i,dm,dy,m2;
char WEEK[9];
if (x==1)
{
printf ("\n ERROR! you forgot to enter the date you want to view\n");
exit (0);
}
i=0; d=-1;
while (date[1][i])
{
if ((date[1][i]=='/'||date[1][i]=='.')&&d==-1) { d=0; i++; continue; }
if ((date[1][i]=='/'||date[1][i]=='.')&&d==0) { d=1; i++; continue; }
if (d==-1) year=year*10+(date[1][i]-'0');
if (d==0) month=month*10+(date[1][i]-'0');
if (d==1) day=day*10+(date[1][i]-'0');
i++;
}
if (month<1||month>12)
{ printf ("\n ERROR! the entered MONTH is invalid\n"); exit (0); }
if (year==2000) { dy=0; m2=1; goto la_100; }
if (year>2000) d=(year-1-2000)/4-(year-1-2000)/100+(year-1-2000)/400+1;
else d=(year-2000)/4-(year-2000)/100+(year-2000)/400;
dy=(year-2000)+d; /*** 该年 1月1号 到2000年1月1号的 " 星期差 " ***/
if((year%4==0&&year%100!=0)||(year%100==0&&year%400==0))
m2=1; else m2=0; /*** 该年是否润 ***/
la_100: /**** la_100 ****/
/*** 该月以前的月所引起的 " 星期差 " ***/
switch (month)
{
case 1: dm=0; month=31; break; /*** month 在此存放该月天数 ***/
case 2: dm=3; month=d==1 29:28; break;
case 3: dm=3+m2; month=31; break;
case 4: dm=6+m2; month=30; break;
case 5: dm=1+m2; month=31; break;
case 6: dm=4+m2; month=30; break;
case 7: dm=6+m2; month=31; break;
case 8: dm=2+m2; month=31; break;
case 9: dm=5+m2; month=30; break;
case 10: dm=m2; month=31; break;
case 11: dm=3+m2; month=30; break;
case 12: dm=5+m2; month=31; break;
}
if (day<0||day>month)
{ printf ("\n ERROR! the entered DAY is invalid\n"); exit (0); }
week=(dy+dm+day-1+6)%7; if(week<0) week+=7;
if (day>0) /*** 判断查看类型 ***/
{
switch (week)
{
case 0: strcpy (WEEK,"SUNDAY"); break;
case 1: strcpy (WEEK,"MONDAY"); break;
case 2: strcpy (WEEK,"TUESDAY"); break;
case 3: strcpy (WEEK,"WEDNESDAY"); break;
case 4: strcpy (WEEK,"THURSDAY"); break;
case 5: strcpy (WEEK,"FRIDAY"); break;
case 6: strcpy (WEEK,"SATURDAY"); break;
}
printf ("\n this day is %s \( %d \)\n\n OK!\n",WEEK,week);
}
else
{
week=++week%7;
printf ("\n the calender of this month as following\n");
printf ("\n *********************************\n");
printf (" SUN MON TUE WEN THU FRI STA\n");
for (i=0;i
for (i=1;i<=month;i++)
{ printf (" %2d ",i); week++; if (week%7==0&&i!=month) printf ("\n"); }
printf ("\n *********************************\n");
printf ("\n OK!\n");
}
}