using System;

using System.Collections.Generic;

public class Solution {

public int[][] UpdateMatrix(int[][] mat) {

    int rows = mat.Length;

    int cols = mat[0].Length;

    

    // Create result matrix

    int[][] result = new int[rows][];

    for (int i = 0; i < rows; i++) {

        result[i] = new int[cols];

    }

    

    // Queue for BFS - stores (row, col)

    Queue<(int row, int col)> queue = new Queue<(int, int)>();

    

    // Initialize: Add all 0s to queue and mark others as -1 (unvisited)

    for (int i = 0; i < rows; i++) {

        for (int j = 0; j < cols; j++) {

            if (mat[i][j] == 0) {

                result[i][j] = 0;

                queue.Enqueue((i, j));