Maximum Product Subarray

Given an integer array nums, find a contiguous non-empty subarray within the array that has the largest product, and return the product.

The test cases are generated so that the answer will fit in a 32-bit integer.

A subarray is a contiguous subsequence of the array.

Example 1:

Input: nums = [2,3,-2,4]
Output: 6
Explanation: [2,3] has the largest product 6.

Example 2:

Input: nums = [-2,0,-1]
Output: 0
Explanation: The result cannot be 2, because [-2,-1] is not a subarray.

Constraints:

• 1 <= nums.length <= 2 * 104
• -10 <= nums[i] <= 10
• The product of any prefix or suffix of nums is guaranteed to fit in a 32-bit integer.

SOLUTION:

class Solution:
    def maxProduct(self, nums: List[int]) -> int:
        n = len(nums)
        maxSoFar = nums[0]
        maxEndingHere = nums[0]
        minEndingHere = nums[0]
        for i in range(1, n):
            temp = max(nums[i], maxEndingHere * nums[i], minEndingHere * nums[i])
            minEndingHere = min(nums[i], maxEndingHere * nums[i], minEndingHere * nums[i])
            maxEndingHere = temp
            maxSoFar = max(maxSoFar, maxEndingHere)
        return maxSoFar