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JarviixAll problems

Rotting Oranges

Medium

Graph · BFS · Matrix~20m

Live AI Interview

00:00

Section 1Understand Problem

Section 01

Understand the problem

Restate the problem precisely. Interviewers reward candidates who pause, define the contract, and name the guarantees before coding.

Problem statement

You are given an `m × n` grid where each cell can have one of three values: `0` representing an empty cell, `1` representing a fresh orange, or `2` representing a rotten orange. Every minute, any fresh orange that is 4-directionally adjacent to a rotten orange becomes rotten. Return the minimum number of minutes that must elapse until no cell has a fresh orange. If this is impossible, return `-1`.

Example

grid = [[2,1,1],[1,1,0],[0,1,1]] → 4

Constraints

m == grid.length · n == grid[i].length · 1 ≤ m, n ≤ 10 · grid[i][j] is 0, 1, or 2

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WPM—Fillers0Pace—Thinking0%

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AI Review

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