# Implementing Fisher-Yates shuffling algorithm

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Now we are getting to the main algorithm.

To shuffle an array a of n elements (indices 0..n-1):

for i from n − 1 downto 1 do

j ← random integer with 0 ≤ j ≤ i

exchange a[j] and a

Add 2 more variables to use in algorithm. I used "k" instead of "j" to see more clearly. And to exchange values of two array values we need a temporary variable.

For loop does not support decreasing values, instead of it i used a while loop. Add a new "system-while" event.

### Add another condition for stopping "while"

. If loop reaches to 1, it will stop.

We have a condition, but our loop is a infinite loop at now. Because "i" value is still the same. We have to decrease it, at the end. But first we will pick a random value with k to exchange. Add a "System-set value" action

UPDATE: There is an error in picture random(i+1) can give a value like i,999999 so using a function like int(floor(random(i+1))) is better idea