/*---------------------------------------------------------------*/
/*  Program chapter6_7                                           */
/*                                                               */
/*  This program initializes a long character string and a short */
/*  character string. It then prints the locations of the short  */
/*  string in the long string. It also prints the number of      */
/*  occurrences of the short string in the long string.          */

#include <stdio.h>
#include <string.h>

int main(void)
{
   /*  Declare and initialize variables.  */
   int count=0;
   char long_str[]="AAACTGACATTGGACCTACTTTGACT",
        short_str[]="ACT";
   char *ptr1=long_str, *ptr2=short_str;

   /*  Count the number of occurrences of short_str in long_str.  */
   /*  While the function strstr does not return NULL, increment  */
   /*  count and move ptr1 to next character of the long string.  */
   while ((ptr1=strstr(ptr1,ptr2)) != NULL)
   {
      printf("location %i \n",ptr1-long_str+1);
      count++;
      ptr1++;
   }

   /*  Print number of occurrences.  */
   printf("number of occurrences: %i \n",count);

   /*  Exit program.  */
   return 0;
}
/*-------------------------------------------------------------*/