<p>Given an array of integers <code>nums</code>, find the maximum length of a subarray where the product of all its elements is positive.</p>

<p>A subarray of an array is a consecutive sequence of zero or more values taken out of that array.</p>

<p>Return <em>the maximum length of a subarray with positive product</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> nums = [1,-2,-3,4]
<strong>Output:</strong> 4
<strong>Explanation:</strong> The array nums already has a positive product of 24.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> nums = [0,1,-2,-3,-4]
<strong>Output:</strong> 3
<strong>Explanation:</strong> The longest subarray with positive product is [1,-2,-3] which has a product of 6.
Notice that we cannot include 0 in the subarray since that&#39;ll make the product 0 which is not positive.</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> nums = [-1,-2,-3,0,1]
<strong>Output:</strong> 2
<strong>Explanation:</strong> The longest subarray with positive product is [-1,-2] or [-2,-3].
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li>
	<li><code>-10<sup>9</sup> &lt;= nums[i] &lt;= 10<sup>9</sup></code></li>
</ul>

class Solution:
    def getMaxLen(self, nums: List[int]) -> int:
        if len(nums) == 1:
            return 1 if nums[0] > 0 else 0
        
        dp = [[0 for _ in range(len(nums)+1)] for _ in range(2)]
        for i, n in enumerate(nums):
            if n > 0:
                #longest negative
                if dp[0][i] != 0:
                    dp[0][i+1] = dp[0][i]+1
                dp[1][i+1] = dp[1][i]+1
            elif n == 0:
                dp[0][i+1] = 0
                dp[1][i+1] = 0
            else:
                dp[0][i+1] = dp[1][i]+1
                if dp[0][i] != 0:
                    dp[1][i+1] = dp[0][i]+1
        res = max(dp[1])
        return res   

            



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