Maximize area between vertical lines
Company: Oracle
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Technical Screen
## Problem
You are given an integer array `h` where `h[i]` represents the height of a vertical line drawn at x-coordinate `i`.
Choose **two different indices** `i < j`. Together with the x-axis, these two lines form a container that can hold water.
The amount of water the container can hold is:
\[
\text{area}(i, j) = (j - i) \times \min(h[i], h[j])
\]
Return the **maximum possible area** over all pairs `(i, j)`.
### Input
- `h`: array of non-negative integers
### Output
- An integer: the maximum area
### Constraints (typical interview constraints)
- `2 <= len(h) <= 10^5`
- `0 <= h[i] <= 10^4`
Quick Answer: This question evaluates algorithmic reasoning with arrays and the ability to optimize pairwise measurements, specifically assessing understanding of how positional distance and element values combine to maximize an area metric.
Return the maximum area formed by two vertical lines and the x-axis.
Constraints
- Inputs are Python literals matching the function signature.
- Return a deterministic exact-match value.
Examples
Input: ([1,8,6,2,5,4,8,3,7],)
Expected Output: 49
Explanation: Classic example.
Input: ([1,1],)
Expected Output: 1
Explanation: Two lines.
Input: ([0,2,0,3],)
Expected Output: 4
Explanation: Zero heights.
Hints
- Pick a representation that makes the requested operation direct.
- Handle empty inputs and boundary cases first.