1441. Build an Array With Stack Operations

https://leetcode.com/problems/build-an-array-with-stack-operations

Description

Given an array target and an integer n. In each iteration, you will read a number from list = {1,2,3..., n}.

Build the target array using the following operations:

• Push: Read a new element from the beginning list, and push it in the array.

• Pop: delete the last element of the array.

• If the target array is already built, stop reading more elements.

Return the operations to build the target array. You are guaranteed that the answer is unique.

Example 1:

**Input:** target = [1,3], n = 3
**Output:** ["Push","Push","Pop","Push"]
**Explanation:**Read number 1 and automatically push in the array -> [1]
Read number 2 and automatically push in the array then Pop it -> [1]
Read number 3 and automatically push in the array -> [1,3]

Example 2:

**Input:** target = [1,2,3], n = 3
**Output:** ["Push","Push","Push"]

Example 3:

**Input:** target = [1,2], n = 4
**Output:** ["Push","Push"]
**Explanation:** You only need to read the first 2 numbers and stop.

Example 4:

**Input:** target = [2,3,4], n = 4
**Output:** ["Push","Pop","Push","Push","Push"]

Constraints:

• 1 <= target.length <= 100

• 1 <= target[i] <= n

• 1 <= n <= 100

• target is strictly increasing.

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