日历项目几乎在C中完成

2 回答

• 1

  您的代码有几个问题：

  • daycode 的计算结果是一个 .

  • 您在 main() 中不使用 daycode ，而不是 nummonths ，导致所有月份似乎在星期日开始 .

  这是一个建议：

  int main(void) {
      int  day, month, year, nummonths;
      printf("Enter Month, Year, and number of Months: ");
      if (scanf("%d %d %d", &month, &year, &nummonths) != 3
      ||  year <= 0 || month < 1 || month > 12) {
          printf("invalid input\n");
          return 1;
      }
  
      for (int i = 0; i < nummonths; i++) {
          printheader(month, year);
          int numdays = getndim(month, year);
          int daycode = getdaycode(month, year);
  
          printf("%*s", daycode * 4, "");   /* print 4 spaces for each skipped day */
          for (day = 1; day <= numdays; day++) {
              printf("%3d", day);
              daycode = (daycode + 1) % 7;
              if (daycode != 0)
                  printf(" ");
              else
                  printf("\n");
          }
          if (daycode != 0)
              printf("\n");
          printf("\n");
  
          month = month + 1;
          if (month > 12) {
              month -= 12;
              year += 1;
          }
      }
      return 0;
  }
  

  您还需要通过更改公式来修复 getdaycode ，以便在函数末尾从 numdays 计算它：

  ...
          }
          int daycode = (numdays + 1) % 7;
          return daycode;
      }
  }
  

  如果您已经学过数组，那么您的代码可以简化很多：

  static int const days[12] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
  static int const leapdays[12] = { 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
  
  int getdaycode(int month, int year) {
      int numdays = 0;
      if (year > 0) {
          // how many days in previous years including exceptions
          numdays = (year - 1) * 365 + (year - 1) / 4 - (year - 1) / 100 + (year - 1) / 400;
      }
      if (month >= 1 && month <= 12) {
          if (month > 2 && (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)))
              numdays += 1;  // count february 29
          for (int i = 0; i < month - 1; i++)
              numdays += days[i];
      }
      // need to offset by one so 1/1/1 falls on a Monday.
      // dates before 1753 are computed according to the
      // proleptic Gregorian calendar.
      return (numdays + 1) % 7;
  }
  
  int getndim(int month, int year) {
      if (month < 1 || month > 12)
          return 0;
      else
      if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0))
          return leapdays[month - 1];
      else
          return days[month - 1];
  }
  

  回复于 2024-05-12T08:19:05+08:00
• 3

  我最近做了类似的事情，因为我想知道三月，四月和五月的周二数 . 所以我写了这段代码

  #include <stdio.h>
  
  int main( void )
  {
      char *monthNames[] = { "March", "April", "May" };
  
      printf( "Enter starting day (0-6): " );
      int day;
      if ( scanf( "%d", &day ) != 1 )
          return 1;
  
      day = -(day % 7);
      for ( int m = 0; m < 3; m++ ) {
          printf( "\n%s\n", monthNames[m] );
          int maxday = (m == 1) ? 30 : 31;
  
          while ( day < maxday ) {
              for ( int col = 0; col < 7; col++ ) {
                  if ( day < 0 )
                      printf( "   " );
                  else if ( day < maxday )
                      printf( " %2d", day+1 );
                  day++;
              }
              printf( "\n" );
          }
  
          if ( day > maxday )
              day = day - maxday - 7;
          else
              day = 0;
      }
  }
  

  一般的想法是变量 day 以 -6 和 0 之间的数字开头 . 只要 day 为负数，代码就会打印三个空格 . 当 day 介于0和月中的天数之间时，代码会打印一个数字 . 在月末， day 的起始值将根据前一个月的结束时间计算下个月 .

  回复于 2024-05-12T08:19:05+08:00