53. Maximum Subarray

Medium

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.

Solution:

class Solution {
    public int maxSubArray(int[] nums) {
        int max_value = nums[0];
        int max_so_far=nums[0];
        for(int i=1;i<nums.length;i++)
        {
            max_so_far = Math.max(max_so_far + nums[i],nums[i]);
            max_value = Math.max(max_so_far,max_value);
        }
        return max_value;
        
    }
}