# Squares of a Sorted Array

## Description

You are given an `m x 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`.

## Approach

1. **Initialize Variables**:
   - Define direction vectors `dx` and `dy` to represent movement in four directions: up, right, down, and left.
   - Create a `visited` matrix to keep track of processed cells.
   - Use a queue to store rotten oranges with their positions and the time step when they were added.

2. **Add Initial Rotten Oranges**:
   - Traverse the grid to find all initially rotten oranges (`grid[i][j] == 2`).
   - Add their positions and the time step (0) to the queue and mark them as visited.

3. **Breadth-First Search (BFS)**:
   - Process the queue while it is not empty:
     - For each rotten orange, explore its 4 neighboring cells using the direction vectors.
     - If a neighboring cell contains a fresh orange (`grid[x][y] == 1`), rot it:
       - Add the neighbor's position and the next time step to the queue.
       - Mark the cell as visited.
     - Track the maximum time required (`min`) to rot all reachable oranges.

4. **Check for Unreachable Fresh Oranges**:
   - After BFS, iterate through the grid to check if there are any unvisited fresh oranges (`grid[i][j] == 1` that are not visited).
   - If any such orange exists, return `-1`.

5. **Return Result**:
   - If all fresh oranges are successfully rotted, return the maximum time (`min`) taken.


## How to Use

1. **Compile**: `g++ -o solution solution.cpp`
2. **Run**: `./solution`

## Contact

If you have any questions, suggestions, or feedback, feel free to reach out to me:

- GitHub: [satendra03](https://github.com/satendra03)
- Email: [satendrakumarparteti.work@gmail.com](mailto:satendrakumarparteti.work@gmail.com)

Happy coding! 😊