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Md Ariful Haque @mah-shamim

Minimum Removals To Make Mountain Array

Given an array nums, return min elements to remove to make it a mountain array. Use dynamic programming to find max mountain subsequence and compute min removals.

1671. Minimum Number of Removals to Make Mountain Array
Difficulty: Hard
Topics: Array, Binary Search, Dynamic Programming, Greedy
You may recall that an array arr is a mountain array if and only if:

arr.length >= 3
There exists some index i (0-indexed) with 0 < i < arr.length - 1 such that:

arr[0] < arr[1] < ... < arr[i - 1] < arr[i]
arr[i] > arr[i + 1] > ... > arr[arr.length - 1]



Given an integer array nums, return the minimum number of elements to remove to make nums a mountain array.
Example 1:

Input: nums = [1,3,1]
Output: 0
Explanation: The array itself is a mountain array so we do...