_53.java

package com.fishercoder.solutions;

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

public class _53 {

    public static class Solution1 {
      /**
       * https://leetcode.com/problems/maximum-subarray/discuss/20211/accepted-on-solution-in-java
       */
      public int maxSubArray(int[] nums) {
        int maxSoFar = nums[0];
        int maxEndingHere = nums[0];
        for (int i = 1; i < nums.length; i++) {
          maxEndingHere = Math.max(nums[i], maxEndingHere + nums[i]);
          maxSoFar = Math.max(maxEndingHere, maxSoFar);
        }
        return maxSoFar;
      }
    }
}