FAQ 4.11 How do I get a random number between X and Y?

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4.11: How do I get a random number between X and Y?

    To get a random number between two values, you can use the "rand()"
    built-in to get a random number between 0 and 1. From there, you shift
    that into the range that you want.

    "rand($x)" returns a number such that "0 <= rand($x) < $x". Thus what
    you want to have perl figure out is a random number in the range from 0
    to the difference between your *X* and *Y*.

    That is, to get a number between 10 and 15, inclusive, you want a random
    number between 0 and 5 that you can then add to 10.

            my $number = 10 + int rand( 15-10+1 ); # ( 10,11,12,13,14, or 15 )

    Hence you derive the following simple function to abstract that. It
    selects a random integer between the two given integers (inclusive), For
    example: "random_int_between(50,120)".

            sub random_int_between {
                    my($min, $max) = @_;
                    # Assumes that the two arguments are integers themselves!
                    return $min if $min == $max;
                    ($min, $max) = ($max, $min)  if  $min > $max;
                    return $min + int rand(1 + $max - $min);


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