I’m getting a time limit error for this problem ===> https://leetcode.com/problems/maximum-subarray/

Any Ideas on how I can save time? This code has passed 199/202 test cases

Here is the problem:

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.

Here is my solution

```
def maxSubArray(self, nums: List[int]) -> int:
x = 0
y = None
for i in range(len(nums)):
for j in range(len(nums)-1 , i -1, -1):
for k in range(j, i - 1, -1):
x += nums[k]
if y == None:
y = x
if x > y:
y = x
x = 0
return y
```