Rule-Based Programming in C

Rule-Based Programming in C




Listing 1


#include "stdoi.h"
int av_speed;
char like_scenery = 0,
   is_pilot = 0,
   fly = 0,
   drive = 0,
   fly_com = 0,
   fly_tcart = 0,
   fly_bon = 0,
   m_cycle = 0,
   car = 0;
main()
{
   int done,
      distance,  /* in miles */
      time:      /* in hours */

   char c;
   char str[10];

   printf("This is a program to help with travel planning. \n");
   printf("\n\n\nHow far are you going? (miles)\n");
   gets(str);
   distances = atio(str);
   printf("\n\nHow much time do you have for the trip? (hours)\n:);
   gets(str);
   time = atio(str);
   av_speed = distance/time;
   printf("\n%d\n",av_speed);
   printf("Do you prefer scenery over speed? (Y/N)\n");
   gets(str);
   if(str[0] = 'Y')   
      like_scenery = 1;
   printf("Are you a pilot? (Y/N)\n");
   gets(str);
   if(str[0] = 'Y')
      is_pilot = 1;
   rules();
   if(fly_com)
      printf("\nFly commercial.");
   if(fly_tcart)
      printf("\nRent a Taylorcraft and fly low.");
   if(fly_bon)
      printf("\nRent a Bonanza and fly high.");
   if(m_cycle)
      printf("\nTake your motorcycle and ride the back roads.");
   if(car)
      printf("\nThere's nothing for it but to drive a car.");
}

rule(s)
{
   if(av_speed > 60)
     fly = 1;
   if (av_speed) <= 60)
     drive = 1;
   if (fly
      && !is_pilot)
         fly_com = 1;
   if(fly
     && is_pilot
     && like_scenery
     && av_speed < 100
        fly_tcart = 1;
   if(fly
   && is_pilot
   && (100 < av_speed)
   && (av_speed < 200))
       fly_bon = 1;

   if(drive
   && like_scenery)
      m_cycle = 1;
   if(drive
   && !m_cycl)
      car = 1;
}