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  • declare a variable x equal to 5

    my $x = 5;

    declare a string x equal to Mary

    my $x = 'Mary';

    declare an array a of the numbers 1,2,4

    my @a = (1, 2, 3);

    declare a hash h where a has key 1, b has key 2

    my %h = (1=>a, 2=>b);

    concatenate strings hello + world into s

    $s = 'hello'.'world';

    remove new line from string s

    chomp($s)

    get length of string s

    length($s)

    convert string to lower case

    lc($s)

    get substring of s

    substr($s, start, len)

    join bob & mary by comma

    join(',','bob','mary');

    read one line from keyboard

    $x = <STDIN>;

    print hello world

    print "Hello world";

    start perl script

    #!/usr/bin/perl
    use strict;
    use CGI ':standard';

    get all data from CGI using post

    @var = param();

    get name data from CGI using post

    $var = param('name');

    get 2nd and 3rd values from days array

    ($x, $y) = @days[1,2];

    remove last item in @days

    $last = pop(@days);

    remove first item in @days

    $first = shift(@days);

    sort @days alphabetically

    @sorted = sort(@days);

    reverse days array

    @rev = reverse(@days);

    get item with key 2 in data hash

    $item = $data{'2'};

    cycle through each element in hash %data

    while ( ($key, $val) = each (%data) ) {print "$key = $val";}

    if string equals yes

    if ($s eq 'yes')

    for each variable in array, print variable

    foreach $x (@array) { print "$x"; }

    size of array

    $#array

    regex match with any capital letter

    /[A-Z]/

    regex letter followed by white space

    /\w\s/

    regex ABC first characters

    /^ABC/

    regex ABC last characters

    /ABC$/

    if x contains either A B or C

    if ($x ~= /[ABC]/)

    print date in $s = "Today is 17 May 2006"

    $s ~= /(\d+) (\w+) (\d+)/;
    print "$1 $2 $3";

    split string by comma into array

    @a = split /,/,$s;

    substitute bob for mary in string

    s/bob/mary/;

    open file and print "hello"

    open (my $in, ">>file.txt");
    print $in "hello";
    close $in;

    open file.txt and read each line, printing to console

    open(my $in, "<file.txt");
    while (my $row = <$in>) { print "$row"; }
    close $in;

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