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3201. Find the Maximum Length of Valid Subsequence I

You are given an integer array  nums . A  subsequence   sub  of  nums  with length  x  is called  valid  if it satisfies: (sub[0] + sub[1]) % 2 == (sub[1] + sub[2]) % 2 == ... == (sub[x - 2] + sub[x - 1]) % 2. Return the length of the  longest   valid  subsequence of  nums . A  subsequence  is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.   Example 1: Input:   nums = [1,2,3,4] Output:   4 Explanation: The longest valid subsequence is  [1, 2, 3, 4] . Example 2: Input:   nums = [1,2,1,1,2,1,2] Output:  6 Explanation: The longest valid subsequence is  [1, 2, 1, 2, 1, 2] . Example 3: Input:   nums = [1,3] Output:   2 Explanation: The longest valid subsequence is  [1, 3] .   Constraints: 2 <= nums.length <= 2 * 10 5 1 <= nums[i] <= 10 7 Solution 1: Dynamic Prog...