##
# Predeclared hashes. Used throughout the script.
my %hashForStuff;
my %hashForEvenNumbers;
my %hashForEvenMoreStuff;
my %hashThatIThinkIMightNeed;
# Is this even necessary?
# my @blahblah;
##
##
if (isValidValue($num)) {
# Do stuff here.
}
return undef unless isValidValue($num2);