Problem Brief

Min Elements to Remove to Make Almost Sorted Array

FULLTIMEOA

An array of integers is almost sorted if at most one element can be deleted from it to make it perfectly sorted, ascending. For example, arrays [2, 1, 7], [13, 9, 2], and [1, 5, 6] are almost sorted because they have 0 or 1 elements out of place. The arrays [4, 2, 1] and [1, 2, 6, 4, 3] are not because they have more than one element out of place.

Given an array of n unique integers, determine the minimum number of elements to remove so that it becomes almost sorted.

1Example 1

Input

arr = [3, 4, 2, 5, 1]

Output

Explanation

Remove 2 to get arr' = [3, 4, 5, 1] or remove 1 to get arr' = [3, 4, 2, 5], both of which are almost sorted. The minimum number of elements that must be removed in this case is 1.

Draft autosaves locally

public int minElementsToRemove(int[] arr) {
  // write your code here
}

Input

arr

[3, 4, 2, 5, 1]

Output