Algorithms and Data Structures implemented in JavaScript for beginners, following best practices.
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/**
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* @function findMaxRecursion
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* @description This algorithm will find the maximum value of a array of numbers.
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*
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* @param {Integer[]} arr Array of numbers
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* @param {Integer} left Index of the first element
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* @param {Integer} right Index of the last element
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*
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* @return {Integer} Maximum value of the array
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*
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* @see [Maximum value](https://en.wikipedia.org/wiki/Maximum_value)
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*
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* @example findMaxRecursion([1, 2, 4, 5]) = 5
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* @example findMaxRecursion([10, 40, 100, 20]) = 100
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* @example findMaxRecursion([-1, -2, -4, -5]) = -1
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*/
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function findMaxRecursion (arr, left, right) {
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const len = arr.length
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if (len === 0 || !arr) {
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return undefined
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}
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if (left >= len || left < -len || right >= len || right < -len) {
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throw new Error('Index out of range')
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}
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if (left === right) {
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return arr[left]
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}
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// n >> m is equivalent to floor(n / pow(2, m)), floor(n / 2) in this case, which is the mid index
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const mid = (left + right) >> 1
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const leftMax = findMaxRecursion(arr, left, mid)
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const rightMax = findMaxRecursion(arr, mid + 1, right)
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// Return the maximum
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return Math.max(leftMax, rightMax)
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}
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export { findMaxRecursion }
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