6. Maximum Product Subarray

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6. 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.


class Solution:
    def maxProduct(self, nums: List[int]) -> int:
        res = max(nums)
        curMax, curMin = 1,1
        for n in nums:
            if n == 0:
                curMax, curMin = 1,1
                continue
            temp = curMax*n
            curMax = max(n*curMax,n*curMin,n)
            curMin = min(temp,n*curMin,n)
            res = max(res,curMax)
        return res