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.
Solution 1 (linear)
class Solution {
public int maxSubArray(int[] nums) {
// corner case check
if (nums == null || nums.length == 0) return 0;
int len = nums.length;
int max = nums[0];
int sum = 0;
for (int i = 0; i < len; i++) {
sum += nums[i];
max = Math.max(sum, max);
// reset sum to 0 when sum < 0.
if (sum < 0) sum = 0;
}
return max;
}
}
