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Maximum Product of Three Numbers

Problem statement​

Given an integer array nums, find three numbers whose product is maximum and return the maximum product.

Example 1:

Input: nums = [1,2,3]Output: 6

Example 2:

Input: nums = [1,2,3,4]Output: 24

Example 3:

Input: nums = [-1,-2,-3]Output: -6

Constraints:

  • 3 <= nums.length <= 104
  • -1000 <= nums[i] <= 1000

My solution​

/**
 * @param {number[]} nums
 * @return {number}
 */
var maximumProduct = function(nums) {
    let maxNumbers = Array.from({
        length: 3
    }, () => Number.MIN_SAFE_INTEGER)
    let minNumbers = Array.from({
        length: 2
    }, () => Number.MAX_SAFE_INTEGER)
    
    for (const num of nums) {
        if (num <= minNumbers[0]) {
//             n is less than minNumbers[0 & 1]
            [minNumbers[0], minNumbers[1]] = [num, minNumbers[0]]
        } else if (num <= minNumbers[1]) {
            [minNumbers[1]] = [num]
        }
        
        if (num >= maxNumbers[0]) {
//             num is greater than maxNumbers[0]
            [maxNumbers[0], maxNumbers[1], maxNumbers[2]] = [num, maxNumbers[0], maxNumbers[1]]
        } else if (num >= maxNumbers[1]) {
            [maxNumbers[1], maxNumbers[2]] = [num, maxNumbers[1]]
        } else if (num >= maxNumbers[2]) {
            [maxNumbers[2]] = [num]
        }
    }
    
    // console.log(minNumbers, maxNumbers)
    
    return Math.max(product([...minNumbers, maxNumbers[0]]), product(maxNumbers))
};

function product(arr) {
    return arr.reduce((acc, curr) => {
        return acc *= curr
    }, 1)
}