/* Inputs a list of strings from the keyboard, sorts them, */
/* then displays them on the screen. */

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

#define MAXLINES 25

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

char *lines[MAXLINES];

main()
{
     int number_of_lines;

     /* Read in the lines from the keyboard. */

     number_of_lines = get_lines(lines);

     if ( number_of_lines < 0 )
     {
         puts(" Memory allocation error");
          exit(-1);
     }

     sort(lines, number_of_lines);
     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("Enter one line at time; enter a blank when done.");

     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 a, b;
     char *x;

     for (a = 1; a < n; a++)
     {
         for (b = 0; b < n-1; b++)
         {
              if (strcmp(p[b], p[b+1]) > 0)
             {
                  x = p[b];
                  p[b] = p[b+1];
                  p[b+1] = x;
             }
         }
     }
}

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

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