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 the minimum time required to rot all fresh oranges adjacent to rotten oranges.

Create a queue to store the coordinates of rotten oranges and perform BFS to rot adjacent fresh oranges.
Track the time taken to rot all fresh oranges and return -1 if not all fresh oranges can be rotten.
Update the grid with the new state of oranges after each second.
Handle edge cases such as empty grid or no fresh oranges present.
Example: For the given grid, the minimum time required is 4 seconds.

Asked in Practo