Rotting Oranges Problem Statement

You are given a grid containing oranges where each cell of the grid can contain one of the three integer values:

0 - representing an empty cell

1 - representing a fresh orange

2 - representing a rotten orange

Every second, any fresh orange that is adjacent (4-directionally) to a rotten orange becomes rotten. Your task is to find the minimum time required after which no cell contains a fresh orange. If it is impossible to rot all the fresh oranges, return -1.

Note:

1. The grid is 0-based indexed. 2. A rotten orange can affect adjacent oranges 4 directionally, i.e., Up, Down, Left, Right.

Example:

Input:

N = 3, M = 3 grid = [ [2, 1, 1], [1, 1, 0], [0, 1, 1] ]

Output:

4

Explanation:

After 4 seconds, all fresh oranges become rotten.

Constraints:

1

Question

Rotting Oranges Problem Statement

You are given a grid containing oranges where each cell of the grid can contain one of the three integer values:

0 - representing an empty cell
1 - representing a fresh orange
2 - representing a rotten orange

Every second, any fresh orange that is adjacent (4-directionally) to a rotten orange becomes rotten. Your task is to find the minimum time required after which no cell contains a fresh orange. If it is impossible to rot all the fresh oranges, return -1.

Note:

1. The grid is 0-based indexed.
2. A rotten orange can affect adjacent oranges 4 directionally, i.e., Up, Down, Left, Right.

Example:

Input:

N = 3, M = 3
grid = [
  [2, 1, 1],
  [1, 1, 0],
  [0, 1, 1]
]

Output:

Explanation:

After 4 seconds, all fresh oranges become rotten.

Constraints:

1 <= N <= 500
1 <= M <= 500
0 <= grid[i][j] <= 2
Time Limit: 1 sec

Accepted Answer

Find minimum time to rot all fresh oranges in a grid if adjacent to rotten oranges.

Use Breadth First Search (BFS) to simulate the rotting process of oranges.
Keep track of the time taken to rot all fresh oranges.
If at the end there are still fresh oranges left, return -1 as it is impossible to rot all oranges.

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