/* dates: Day numbers to other format

   Example:

	Day 183 is 2.7 
	Day 86 is 27.3 
*/

#include <stdio.h>
#include <stdlib.h>

int day_nbr, month, days_to_beginning, days_at_end;

int days_in_month[12]={31,28,31,30,31,30,31,31,30,31,30,31};

int main (void) {

   day_nbr = rand() % 400;

   while (day_nbr > 0 && day_nbr <= 365) {


	/* Find month and day: */

	month = -1;
	days_to_beginning = 0;
	days_at_end = 0;

	while (day_nbr > days_at_end && month < 11) {
	    month++;
	    days_to_beginning = days_at_end;
	    days_at_end = days_at_end + days_in_month[month];
	}

	/* Generate output: */

	printf("Day %d is %d.%d \n",
	        day_nbr, day_nbr - days_to_beginning, month+1);

	/* Get the next day number: */

	day_nbr = rand() % 400;
   }

   return(0);
}

   	Modify the above program to use normal month numbers (1 for
   	January, 2 for February, ...) as values of the variable "month".