#!/usr/bin/env ruby
# 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.

def selection_sort(entries)
  entries.length.times do |i|
    # find minimum value in the range i..(entries.length-1) 
    min_idx = i
    (i+1..entries.length-1).each do |j| 
       min_idx = j if (entries[j] < entries[min_idx]) 
    end 
    # if needed, swap the i-th entry with the min_idx entry
    next if i == min_idx
    entries[i],entries[min_idx]=entries[min_idx],entries[i];
  end 
end

if ARGV.length != 1
  $stderr.puts "Usage:\n\t#{$0} (file with numbers to sort)"
  exit -1
end

# read in the entries
entries = Array.new
IO.foreach(ARGV[0]) { |line| entries.push Float(line) }

# sort them
selection_sort(entries)

# display the results
entries.each { |entry| puts entry }