Path With Minimum Effort
Difficulty: Medium
Category: DSA
Topics: Array, Binary Search, Depth-First Search, Breadth-First Search, Union Find, Heap (Priority Queue), Matrix
Asked at: Google, Houzz, ByteDance
You are a hiker preparing for an upcoming hike. You are given `heights`, a 2D array of size `rows x columns`, where `heights[row][col]` represents the height of cell `(row, col)`. You are situated in the top-left cell, `(0, 0)`, and you hope to travel to the bottom-right cell, `(rows-1, columns-1)` (i.e., **0-indexed**). You can move **up**, **down**, **left**, or **right**, and you wish to find a route that requires the minimum **effort**.
A route's **effort** is the **maximum absolute difference**** **in heights between two consecutive cells of the route.
Return _the minimum **effort** required to travel from the top-left cell to the bottom-right cell._
**Example 1:**
**Input:** heights = [[1,2,2],[3,8,2],[5,3,5]]
**Output:** 2
**Explanation:** The route of [1,3,5,3,5] has a maximum absolute difference of 2 in consecutive cells.
This is better than the route of [1,2,2,2,5], where the maximum absolute difference is 3.
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**Example 2:**
**Input:** heights = [[1,2,3],[3,8,4],[5,3,5]]
**Output:** 1
**Explanation:** The route of [1,2,3,4,5] has a maximum absolute difference of 1 in consecutive cells, which is better than route [1,3,5,3,5].
```
**Example 3:**
**Input:** heights = [[1,2,1,1,1],[1,2,1,2,1],[1,2,1,2,1],[1,2,1,2,1],[1,1,1,2,1]]
**Output:** 0
**Explanation:** This route does not require any effort.
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**Constraints:**
- `rows == heights.length`
- `columns == heights[i].length`
- `1 <= rows, columns <= 100`
- `1 <= heights[i][j] <= 106`