#!/usr/local/bin/perl
# Jaime Prilusky, 2009
# data from http://www.genomesize.com/

# initialize a 'mammals' hash with key-value pairs

  my %mammals = (
    "Ornithorhynchus anatinus" => 54,
    "Tachyglossus aculeatus"   => 64,
    "Gorilla gorilla"          => 48,
    "Homo sapiens"             => 48,
    "Pan troglodytes"          => 48,
    "Pongo pygmaeus"           => 48,
  );

# extract single value from a hash. Print the value for 'Homo sapiens'
  print "\n";
  print "Homo sapiens diploid chromosome number is ", $mammals{'Homo sapiens'}, "\n";

# get and print all keys
  print "\n";
  my @keys = keys %mammals;
  print "All keys are: @keys\n";

# get and print all values
  print "\n";
  my @values = values %mammals;
  print "All values are: @values\n";

# print the entire hash, no sort
  print "\n";
  while(($specie,$diploidNumber) = each %mammals) {
    printf ("%30s %d\n",$specie,$diploidNumber);
  }

# print the entire hash, no sort
  print "\n";
  foreach $specie (keys %mammals) {
    my $diploidNumber = $mammals{$specie};
    printf ("%30s %d\n",$specie,$diploidNumber);
  }

# print the entire hash, sorted by specie
  print "\n";
  foreach $specie (sort keys %mammals) {
    my $diploidNumber = $mammals{$specie};
    printf ("%30s %d\n",$specie,$diploidNumber);
  }

# print the entire hash, sorted by diploid number
  print "\n";
  foreach $specie (sort {$mammals{$a} <=> $mammals{$b}} keys %mammals) {
    my $diploidNumber = $mammals{$specie};
    printf ("%30s %d\n",$specie,$diploidNumber);
  }