#679 · #2369 · Check if There is a Valid Partition For The Array(检查数组是否存在有效划分)

Given a 0-indexed integer array nums, a partition into contiguous subarrays is valid when every subarray is one of: length 2 with equal elements, length 3 with all elements equal, or length 3 with three consecutive increasing integers. Return whether such a partition exists. Constraints: 2 <= nums.length <= 10^5, 1 <= nums[i] <= 10^6.