#### Find Max Recursion

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/**
* @function findMaxRecursion
* @description This algorithm will find the maximum value of a array of numbers.
*
* @param {Integer[]} arr Array of numbers
* @param {Integer} left Index of the first element
* @param {Integer} right Index of the last element
*
* @return {Integer} Maximum value of the array
*
* @see [Maximum value](https://en.wikipedia.org/wiki/Maximum_value)
*
* @example findMaxRecursion([1, 2, 4, 5]) = 5
* @example findMaxRecursion([10, 40, 100, 20]) = 100
* @example findMaxRecursion([-1, -2, -4, -5]) = -1
*/
function findMaxRecursion(arr, left, right) {
const len = arr.length

if (len === 0 || !arr) {
return undefined
}

if (left >= len || left < -len || right >= len || right < -len) {
throw new Error('Index out of range')
}

if (left === right) {
return arr[left]
}

// n >> m is equivalent to floor(n / pow(2, m)), floor(n / 2) in this case, which is the mid index
const mid = (left + right) >> 1

const leftMax = findMaxRecursion(arr, left, mid)
const rightMax = findMaxRecursion(arr, mid + 1, right)

// Return the maximum
return Math.max(leftMax, rightMax)
}

export { findMaxRecursion }