/* Copyright 2005 Daniel Cer (daniel.cer@cs.colorado.edu)

This work is licensed under the Creative Commons Attribution-NonCommercial-
ShareAlike License. To view a copy of this license, visit 
http://creativecommons.org/licenses/by-nc-sa/2.5/ or send a letter to 
Creative Commons, 543 Howard Street, 5th Floor, San Francisco, California, 
94105, USA.
*/

#include <stdio.h>
#include <errno.h>

#define SZ_INBUF 1024

void selection_sort(float *entries, int N_entries) { int i, j, min_idx;
  for (i = 0; i < N_entries; i++) { float swap_tmp;
    /* find minimum value in the range i..(N_entries-1) */
    for (j = i+1, min_idx = i; j < N_entries; j++) 
      if (entries[j] < entries[min_idx]) min_idx = j;
    /* if needed, swap i-th entry with min_idx entry */
    if (i == min_idx) continue;
    swap_tmp = entries[i];
    entries[i] = entries[min_idx];
    entries[min_idx] = swap_tmp;
  }
}

int main(int argc, char *argv[]) { 
  FILE *fh; int i, N_entries; float *entries; char *file_name, inbuf[SZ_INBUF];
  if (argc != 2) {
    fprintf(stderr, "Usage:\n\t%s (file with numbers to sort)\n", argv[0]);
    return -1;
  }

  file_name = argv[1];
  if (!(fh = fopen(file_name, "r"))) {
    fprintf(stderr, "Error opening \"%s\": %s\n", file_name, strerror(errno));
    return -1;
  } 

  /* count entries to sort */
  for (i = 0; fgets(inbuf, SZ_INBUF, fh); i++); N_entries = i;

  /* allocate space to store them */
  if (!(entries = malloc(sizeof(float)*N_entries))) {
    fprintf(stderr, "Out of memory!\n"); return -1; }
  
  fseek(fh, 0, SEEK_SET);

  /* read them in */
  for (i=0; fgets(inbuf, SZ_INBUF, fh); i++) sscanf(inbuf,"%f\n",&entries[i]);
  fclose(fh);

  /* sort them */
  selection_sort(entries, N_entries); 

  /* display the results */
  for (i = 0; i < N_entries; i++) printf("%f\n", entries[i]);
 
  free(entries);
  return 0;
}