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hey everybody in today's video I'm going
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to show you how we can Shuffle the
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elements of an array using JavaScript
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this is an optional video you might find
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this topic helpful if you're interested
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in making a game using JavaScript or any
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sort of application where you need some
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Randomness in this example we'll create
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a deck of cards our deck of cards will
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be an array we have an a for Ace the
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numbers 2 through 10 let me finish
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typing those
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in J for Jack Q for Queen k for King I'm
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not going to include any suits for these
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cards such as Ace of Hearts Ace of clubs
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that might be overkill for this example
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one method you might see floating around
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online to shuffle the elements of an
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array is to use the sort method then
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pass in an arrow function where you take
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math.random minus 0.5 I would not
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recommend using this method just because
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the results of this method aren't
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perfectly uniform let me console.log
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cards this array appears shuffled but
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it's not that uniform but not only that
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the Lar larger the array becomes this
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method becomes increasingly more
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inefficient I would not recommend using
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the sort method to shuffle an array
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instead I would recommend using the fer
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Yates algorithm we'll create a dedicated
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function for
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this so we will Define a function to
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shuffle there will be one parameter an
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array then to invoke this function we'll
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type the function name pass an our array
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of
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cards so what do we want to do exactly
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we're first going to Loop through the
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elements of this array we'll start at
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the end and work our way towards the
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beginning we'll use a for Loop to
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decrement So within our Shuffle function
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we'll create a for Loop we will declare
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index of I let I equal R array do
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length then minus one that's the first
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statement our array has 13 elements but
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the last index is 12 because arrays
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start with zero if the array's length is
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13 we need to subtract 1 to get 12 which
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would give us the ending index of 12
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we'll continue this loop as long as I is
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greater than
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zero then iusus to decrement now we have
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to generate a random number between the
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end and the beginning somewhere within
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this range we'll create const random
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random will store a random number take
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math. random method times
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I our index + one we'll need to round
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this number we're now going to enclose
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this equation with math. floor to round
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down math. floor and enclose this
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equation all right during the first
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iteration of this Loop we should
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generate a random number between the end
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and the beginning we'll swap our king
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with a random element within this array
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so to swap two elements of this array we
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can use destructuring in this context to
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use destructuring we'll take our
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original position array at index of I
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during our first iteration that will be
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the king we'll swap our King with our
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array at a random index the one that
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will be randomly
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generated equals our array at index of
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random comma array at index of
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I then to finish using destructuring we
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need to enclose both sides of this
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equation with with an
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array there and that will swap two
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elements of your
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array now if I run this program this
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will Shuffle the elements of my array I
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would recommend using a dedicated
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Shuffle function because in a game it's
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likely you're going to shuffle something
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more than once throughout that game like
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I said this isn't a necessary topic to
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continue on with the series but if
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you're ever interested in making a game
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using JavaScript or need some element of
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Randomness well then this function would
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work great and that is how to to shuffle
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the elements of an array using
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JavaScript