Path With Minimum Effort

Medium

Graph · Dijkstra · Binary Search~25m

00:00

Section 1Understand Problem

Section 01

Understand the problem

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Problem statement

You are a hiker preparing for an upcoming hike. You are given `heights`, a 2D array of size `rows × 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)`. 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

heights = [[1,2,2],[3,8,2],[5,3,5]] → 2

Constraints

rows == heights.length · columns == heights[i].length · 1 ≤ rows, columns ≤ 100 · 1 ≤ heights[i][j] ≤ 10⁶

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