MaximumSubarray.js

// Source : https://leetcode.com/problems/maximum-subarray
// Author : Dean Shi
// Date   : 2017-03-02

/***************************************************************************************
 *
 * Find the contiguous subarray within an array (containing at least one number) which
 * has the largest sum.
 *
 * For example, given the array [-2,1,-3,4,-1,2,1,-5,4],
 * the contiguous subarray [4,-1,2,1] has the largest sum = 6.
 *
 * click to show more practice.
 *
 * More practice:
 *
 * If you have figured out the O(n) solution, try coding another solution using the
 * divide and conquer approach, which is more subtle.
 *
 *
 ***************************************************************************************/

/**
 * @param {number[]} nums
 * @return {number}
 */
var maxSubArray = function(nums) {
    let max = nums[0]

    nums.reduce((sum, num) => {
        sum = Math.max(sum + num, num)
        max = Math.max(max, sum) 
        return sum
    })
    return max
};