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List::Util - List Utility

List::Util is a module that provides various operations on list or array.

# Load List::Util
use List::Util;

# When importing a function
use List::Util 'max', 'min';

max function - maximum value

Use max to find the maximum value of an array element.

# Find the maximum value
my @nums = (5, 3, 4);
my $max = List::Util::max(@nums);

# Five
print "$max\n";

min function - minimum value

Use min to find the minimum value of an array element.

# Find the minimum value
my @nums = (5, 3, 4);
my $min = List::Util::min(@nums);

# 3
print "$min\n";

sum function - sum

Use sum to sum the elements of the array.

# Find the total
my @nums = (5, 3, 4);
my $min = List::Util::sum(@nums);

# 12
print "$min\n";

shuffle function - Randomly change the order of elements

Use shuffle to randomly change the order of the elements in the array.

# Randomly change the order of elements
my @nums = (5, 3, 4, 7, 2, 9);
my @nums_shuffle = List::Util::shuffle(@nums);

# 2 5 7 3 9 4 (changes every time)
print "@nums_shuffle\n";

first function - get the first element that matches the condition

Use first to get the first element that matches the condition. Each element of the array is passed to default variable "$_".

# Get the first match
my @nums = (5, 3, 4, 9, 2, 7);
my $match_first = List::Util::first {$_ > 5} @nums;

# 9
print "$match_first\n";

Since the syntax is similar to the map function, please also refer to map function.

uniq function - get a unique set

To get a unique set, use the uniq function.

# Get a unique set
my @nums = (5, 5, 5, 1, 3, 3);
my @no_dup_nums = List::Util::uniq(@nums);

# 5 1 3
print "@no_dup_nums\n";