maximum_subarray.go

/**
53. Maximum Subarray

Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum.

A subarray is a contiguous part of an array.

Example 1:
Input: nums = [-2,1,-3,4,-1,2,1,-5,4]
Output: 6
Explanation: [4,-1,2,1] has the largest sum = 6.

Example 2:
Input: nums = [1]
Output: 1

Example 3:
Input: nums = [5,4,-1,7,8]
Output: 23
 

Constraints:

1 <= nums.length <= 105
-104 <= nums[i] <= 104
 

Follow up: If you have figured out the O(n) solution, try coding another solution using the divide and conquer approach, which is more subtle.
 */

func maxSubArray(nums []int) int {
    sum, result := nums[0], nums[0]
    
    for i := 1; i < len(nums); i++ {   
        if sum + nums[i] > nums[i] {
            sum += nums[i]
        } else {
            sum = nums[i]
        }
        
        if result < sum {
            result = sum
        }
    }
    return result
}