Make Array Non Decreasing · Interview Problem

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Make Array Non Decreasing

Modify an array using the allowed operation(s) so that the final sequence becomes non-decreasing.

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Problem Statement

Problem

Given an integer array, apply the allowed operation(s) defined by the problem so that the array becomes non-decreasing (that is, each element is at least the previous one).

Your goal is to determine the required result for the array after performing the process described in the statement, or to decide whether it is possible depending on the exact operation rules.

A sequence is non-decreasing if for every index $i > 0$ , we have:

$a[i] \ge a[i-1]$

Work with the array in order and reason about how earlier values constrain later ones.

Input Format

An integer $n$ describing the size of the array.
An array of $n$ integers.
Any additional operation parameters if applicable to the variant.

Output Format

Return the transformed array, or
return the minimum number of operations / a feasibility result, depending on the exact variant.

Constraints

The array size is positive.
Values may be negative or positive integers.
The final array must satisfy $a[i] \ge a[i-1]$ for all valid $i$ .

Examples

Sample cases returned by the problem API.

Example 1

Input

nums = [5, 4, 3, 2]

Output

[5, 5, 5, 5]

Explanation

Illustrative example: after enforcing a non-decreasing sequence, later values may need to be raised to match earlier constraints.

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