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

#define LINES 10

void merge_sort(int to_sort[LINES], int first, int last);
void merge(int arr[LINES], int f1, int l1, int f2, int l2);

int main()
{
  int bytes_read, q;
  int nbytes = 100;
  char *my_string = NULL;
  char arrstr[LINES][100];
  FILE *infile;
  char t;
  int fi;
  float ff;

  int array[]= {3, 5, -7, 5679, 12, -4, 8675, 549, -77, -3};

  printf("Before sort:   ");
  for (fi=0; fi<LINES; fi++)
    {
      printf("%d, ",array[fi]);
    }
  printf("\n");

  merge_sort(array, 0, LINES-1);


  printf("Before sort:   ");
  for (fi=0; fi<LINES; fi++)
    {
      printf("%d, ",array[fi]);
    }
  printf("\n");


  /*
  infile = fopen("testtext.txt", "r");
  puts ("Reading data from testtext.txt\n");

  // These 2 lines are the heart of the program. 
  my_string = (char *) malloc (nbytes + 1);


  for (q = 0; q < LINES; q++)
    {
      fscanf(infile,"%d %f",&fi, &ff);
      fgetc(infile);
      bytes_read = getline (&my_string, &nbytes, infile);
      strcpy(arrstr[q],my_string);
      
      if (bytes_read == -1)
	{
	  puts ("ERROR!");
	}
      else
	{
	  puts ("You typed:");
	  puts (my_string);
	  puts(arrstr[q]);
	  printf("Numbers are : %d %f",fi, ff);
	  //	  printf("\nthe fourth char is %c and %c\n", *(my_string+3),arrstr[q][3]);
	  //	  printf("\nthe fifth char is %c and %c\n", my_string[4],*((arrstr + q ) + 4  ) );
	}
    }


  */
  return 0;
}

void merge_sort(int to_sort[LINES], int first, int last)
{

  printf("\n In merge_sort, first is %d, last is %d \n",first,last);

  if (first < last)
    {
      merge_sort( to_sort, first, (first+last)/2);
      merge_sort( to_sort, (first+last)/2+1, last);

      merge(to_sort, first, (first+last)/2,
	    (first+last)/2+1, last);
    }
}

void merge(int arr[LINES], int f1, int l1, int f2, int l2)
{
  int t[LINES];
  int i, i1, i2, num;

  i= 0;
  i1 = f1;
  i2=f2;
  num = l1 - f1 + l2 - f2 +2;

  while(( i1 <= l1) && (i2 <= l2))
    {
      if (arr[i1] < arr[i2])
	t[i++] = arr[i1++];
      else
	t[i++]= arr[i2++];
    }

  if (i1 > l1)
    while (i2 <= l2)
      t[i++]=arr[i2++];   

  else
    while (i1 <= l1)
      t[i++]=arr[i1++];    
  //    move( arr, i1, l1, t, i);

  i=0;
    while ( i<= num-1)
      arr[f1++]=t[i++];   


}