#Hashes or Associative Arrays
$food{'apple'} = 'fruit';
$food{'beef'} = 'meat';
$food{'carrot'} = 'vegetable';

print "1.\n";
print $food{'apple'}." ";
print $food{'beef'}." ";
print $food{'carrot'}."\n\n";

#reassign variable, % is for hashes/associative array
%food = ( 'apple' => 'fruit', 
		'beef' => 'meat', 
		'carrot' => 'vegetable', 
		);
		
print "2.\n";
print $food{"apple"}." ";
print $food{'beef'}." ";
print $food{"carrot"}."\n\n";  #both ", ' works

print "3.\n";
#keys function to retrieve all keys, return a list
foreach $var (keys %food) {  #keys
	print "$var ";
}
print "\n\n";

print "4.\n";
foreach $var (keys %food) {  #hashed values
	print "$food{$var} ";
}
print "\n\n";

print "5.\n";
#values function to retrieve all values
@foodtype = values %food;
for ($i = 0; $i<@foodtype; $i++) {
	print "$foodtype[$i] ";
}
print "\n\n";

#reverse key and value
print "6.\n";
%ByType = reverse %food;
print $ByType{'fruit'}." ";
print $ByType{'meat'}." ";
print $ByType{'vegetable'}."\n\n";

#copy hashes
print "7.\n";
%food2 = %food; #assign 1 hash to another
foreach $var (keys %food2) {  #keys
	print "$var=>$food2{$var}; ";
}
print "\n\n";

#canot really control key order in hashes
#sort keys in list, not really supported in hashes
print "8.\n";
my @sortorder = sort keys %food2;
for ($i = 0; $i<@sortorder; $i++) {
	print "$sortorder[$i]=>$food2{$sortorder[$i]} ";
}
print "\n\n";

#removing keys from a hash
print "9.\n";
delete $food2{'beef'};
foreach $var (keys %food2) {  #keys
	print "$var=>$food2{$var}; ";
}
print "\n\n";

#add key to hash
print "10.\n";
$food2{'pork'} = 'meat';
$food2{'chicken'} = 'meat';
foreach $var (keys %food2) {  #keys
	print "$var=>$food2{$var}; ";
}
print "\n\n";

#size of hash
print "11.\n";
print "Hash size of food2: ",scalar keys %food2,"\n";