How to Find LCM in JavaScript | Step-by-Step Tutorial

What is LCM? | Maths Explanation for Perl Kids

Akin to finding H.C.F., L.C.M. is commonly found by repeated factorization. Only this time, the factors do not have to be common amongst the set of numbers.

If we have the set of numbers 8, 12 and 18 for example, their L.C.M. is found thus:

Hence, L.C.M. of 8, 12 and 18 = 2 X 2 X 2 x 3 x 3 = 72

Step-by-Step Guide to L.C.M. by Factorisation in Perl

We shall follow the steps below in writing our Perl LCM code.

Step 1:

Do a numerical reverse sort on the (resulting) set so its first member is the largest in the set.

Step 2:

Starting with 2, iteratively check through the set of numbers for individual factors.

Step 3:

For each individual factor, divide affected member(s) of the number set by the factor.

Step 4:

Repeat the above steps recursively until there are no more individual factors.

Create a new Perl class file; File, New File.
Call it FindLCM.pm

Type out the adjoining Perl code for finding Lowest Common Multiple (L.C.M.)

Note: You can comment out the Perl code for the main class from the previous lesson if you have been following.

So! Perl Fun Practice Exercise - Find LCM

As a fun practice exercise, feel free to try out your own numbers, and see how the Perl code finds the LCM of those numbers.

Perl Code for Find LCM - Module File.

<!DOCTYPE html>

<html lang="en">
    <head>
        <meta charset="utf-8" />
        <title>Find H.C.F.</title>
        <script src="LCM.js"></script>
    </head>
    <body>
        <h4>Lowest Common Multiple of a Set of Numbers.</h4>
        <div id="myLCM"></div>

        <script>/*
         * 'set_of_numbers' holds the numbers whose LCM we are trying to find.
         * Add as many of these numbers as you wish by extending the array.
         */
            var set_of_numbers = [];
            set_of_numbers[0] = 4;
            set_of_numbers[1] = 5;
            set_of_numbers[2] = 6;

            var result = getLCM(set_of_numbers); // call to our function

            document.getElementById("myLCM").innerHTML = "The L.C.M. of " +
                    set_of_numbers.join(", ") + " is: " + result;
        </script>
    </body>
</html>

Perl Code for Find LCM - Main Class.

I have a better version / See other versions.