One Pager Cheat Sheet
- The text requests the implementation of a shuffle method that accepts an
arrayas a parameter and generates a random permutation of its elements. - The article describes the process of creating a shuffling algorithm that takes an array and randomizes its order by visiting each element in the array and exchanging it with another randomly chosen element using a
swapping technique, ensuring that every potential arrangement of elements is likely. - The shuffling function in
JavaScriptworks by looping through an array, computing a random index, and swapping elements, introducing randomness to rearrange the elements.
This is our final solution.
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// Shuffle function implementation - fill in your code!function shuffle(arr) { for (let i = 0; i < arr.length; i++) { const j = i + Math.floor(Math.random() * (arr.length - i)); [arr[i], arr[j]] = [arr[j], arr[i]]; }}const arr = [1, 2, 3, 4];const permutations = [ [1, 2, 3, 4], [1, 2, 4, 3], [1, 3, 2, 4], [1, 3, 4, 2], [1, 4, 2, 3], [1, 4, 3, 2], [2, 1, 3, 4], [2, 1, 4, 3], [2, 3, 1, 4], [2, 3, 4, 1], [2, 4, 1, 3], [2, 4, 3, 1], [3, 1, 2, 4], [3, 1, 4, 2], [3, 2, 1, 4], [3, 2, 4, 1], [3, 4, 1, 2], [3, 4, 2, 1], [4, 1, 2, 3], [4, 1, 3, 2], [4, 2, 1, 3], [4, 2, 3, 1], [4, 3, 1, 2], [4, 3, 2, 1]];// Shuffle the arrayshuffle(arr);// Validate the shuffled arrayconst isValidPermutation = permutations.some(permutation => JSON.stringify(permutation) === JSON.stringify(arr));if (isValidPermutation) { console.log('The shuffled array is a valid permutation:', arr);} else { console.log('Something went wrong! The shuffled array does not match any of the valid permutations.');}OUTPUT
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