countdown

Program

/* File: countdown.c
 * Author: Richard Chang
 * Date: pre 1997
 * Modified by: Sue Evans
 * Date: 11/8/05
 * Section: 101
 * EMail: bogar@cs.umbc.edu
 * 
 * A very simple example of a recursive function.
 */

#include <stdio.h>

void Countdown (int) ;

int main() 
{
   int n ;

   printf("Engaging the auto-destruct sequence\n") ;
   printf("Enter number of seconds to auto-destruct: ") ;
   scanf("%d", &n) ;
 
   printf("Counting down from %d\n", n) ;
   Countdown(n) ;

   return 0;
}


/******************************************
* Function Name: Countdown ()
* Countdown() uses recursion to count down from k to 0
*
* Inputs:      integer to count down from
* Outputs:     returns nothing
* Side effect: prints to screen the counting down and 
*              "KABOOM!!!"
******************************************/

void Countdown (int k) 
{
  /* The BASE CASE */
  if (k == 0) 
  {
     printf("KABOOM!!!\n") ;
  } 
  /* The GENERAL RULE - recursive case */
  else 
  {
     printf("   %d seconds to auto-destruct\n", k) ;
     Countdown (k - 1) ;
  }
}

Output