I am having problems with my code it says that the value compare
is not being intitalized please help. I need to enter seven words total then sort them out.please help.

// it might work2.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"


  /* Inputs a list of strings from the keyboard, sorts them */
  /* in ascending or descending order, and then displays them */
  /* on the screen. */
  #include <stdlib.h>
  #include <stdio.h>
  #include <string.h>
#define MAXLINES 25


 int get_lines(char *lines[]);
  void sort(char *p[], int n, int sort_type);
  void print_strings(char *p[], int n);
  int alpha(char *p1, char *p2);
  

  char *lines[MAXLINES];




int _tmain(int argc, _TCHAR* argv[])



  

 

  {
     int number_of_lines, sort_type;


	  int f=0;
     /* Read in the lines from the keyboard. */

     number_of_lines = get_lines(lines);

	 if ( number_of_lines < 0 ){
     
        puts("Enter no to exit");
        exit(-1);
     }
	
     puts("\nDo You Have Any more words\n" );
     scanf_s("%d", &sort_type);

     sort(lines, number_of_lines, sort_type);
     print_strings(lines, number_of_lines);
     return 0;
  }

  int get_lines(char *lines[])
  {
      int n = 0;
      char buffer[80];  /* Temporary storage for each line. */

	  puts("Do You Have Any More Words:");

  while (n < MAXLINES && gets(buffer) != 0 && buffer[0]!=0)
      {
          if ((lines[n] = (char *)malloc(strlen(buffer)+1)) == NULL)
          return -1;
          strcpy( lines[n++], buffer );
      }
      return n;

  } /* End of get_lines() */

  void sort(char *p[], int n, int sort_type)
  {
      int a, b;
      char *x;
	  

      /* The pointer to function.  */

      char(*compare)(char *s1, char *s2);

      /* Initialize the pointer to point to the proper comparison */
      /* function depending on the argument sort_type. */

     

      for (a = 1; a < n; a++)
      {
          for (b = 0; b < n-1; b++)
          {
              if (compare(p[b],p[b+1]) > 0)
              {
                  x = p[b];
                  p[b] = p[b+1];
                  p[b+1] = x;
              }
         }
      }
  }  /* end of sort() */

  void print_strings(char *p[], int n)
  {
     int count;

      for (count = 0; count < n; count++)
          printf("%s\n ", p[count]);
  }

  int alpha(char *p1, char *p2)
  /* Alphabetical comparison. */
  {
      return(strcmp(p2, p1));
  }
Ancient Dragon commented: hijack -5

Example using alpha as the comparison function:

int (*compare)(char*,char*) = &alpha;

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