C语言万年历代码分享

 #include <stdio.h>main(){void print_head(int x,int y);       /*打印头文件*/void print_month(int x,int y);      /*打印月历*/int days_of_month(int x,int y);     /*计算指定年月的天数*/int leap(int x,int y);              /*计算指定年月1号是星期几*/int i,days,year,month,firstday;char choose;    do       {printf ("nnplease input the year(0000~9999):nn");        scanf ("%d",&year);   if (year<0||year>9999) printf ("WANNING:ERROR,please input again!");}    while (year<0||year>9999);    printf ("nn");    do       {printf ("please input the month(0~12)nnn");        scanf ("%d",&month);   if (month<=0||month>12) printf ("WANNING:ERROR,please input again!");}    while (month<=0||month>12);    printf ("nn");    days=days_of_month(year,month);       /*调用函数*/    firstday=leap(year,month);    print_head(year,month);    print_month(firstday,days);    choose=getchar();    printf ("nnn");    printf("would you like to continue(y/n):nn");      scanf("%c",&choose);    if (choose=='y'||choose=='Y') main();}days_of_month(int x,int y){int z;switch (y){case 1:  case 3:  case 5:  case 7:  case 8:  case 10:  case 12: z=31;break;  case 4:  case 6:  case 9:  case 11: z=30;break;  case 2:   {if ((x%4==0&&x%100!=0)||(x%400==0)) z=29;     else z=28;break;   }   }return z;}leap(int x,int y){int z,i,moday;z=(x+(x-1)/4-(x-1)/100+(x-1)/400)%7;for (i=1;i<y;i++)  {moday=days_of_month(x,i);       /*钳套调用函数*/   z=(z+moday)%7;  }return z;}void print_head(int x,int y){printf ("nn********************************************************************************nn");printf ("tttt%d       %dnn",x,y);printf ("ttt SUN MON TUE WED THU FRI SATn");printf ("ttt");}void print_month(int x,int y){int i;char space[7]={' '};for (i=1;i<=x;i++)    printf ("%4c",space[i]);for (i=1;i<=y;i++)    {if ((i+x)%7==1) printf ("nttt%4d",i);      else printf ("%4d",i);}printf ("nn********************************************************************************nn");}