Here, We see 01 Matrix LeetCode Solution. This Leetcode problem is done in many programming languages like C++, Java, JavaScript, Python, etc. with different approaches.

List of all LeetCode Solution

01 Matrix LeetCode Solution

Problem Statement

Given an m x n binary matrix mat, return the distance of the nearest 0 for each cell.

The distance between two adjacent cells is 1.

Example 1:

Input: mat = [[0,0,0],[0,1,0],[0,0,0]]
Output: [[0,0,0],[0,1,0],[0,0,0]]

Example 2:

Input: mat = [[0,0,0],[0,1,0],[1,1,1]]
Output: [[0,0,0],[0,1,0],[1,2,1]]

01 Matrix Leetcode Solution C++

class Solution {
public:
    vector<vector<int>> updateMatrix(vector<vector<int>>& mat) {
        int rows = mat.size();
        int cols = mat[0].size();
        vector<pair<int, int>> directions = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};
        queue<pair<int, int>> q;
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < cols; j++) {
                if (mat[i][j] == 0) {
                    q.push({i, j});
                } else {
                    mat[i][j] = INT_MAX;
                }
            }
        }
        while (!q.empty()) {
            pair<int, int> cell = q.front();
            q.pop();
            int row = cell.first;
            int col = cell.second;
            for (pair<int, int> direction : directions) {
                int newRow = row + direction.first;
                int newCol = col + direction.second;
                if (newRow >= 0 && newRow < rows && newCol >= 0 && newCol < cols && mat[newRow][newCol] > mat[row][col] + 1) {
                    mat[newRow][newCol] = mat[row][col] + 1;
                    q.push({newRow, newCol});
                }
            }
        }
        return mat;        
    }
};Code language: PHP (php)

01 Matrix Leetcode Solution Java

class Solution {
    public int[][] updateMatrix(int[][] mat) {
        int rows = mat.length;
        int cols = mat[0].length;
        int[][] directions = {{0, 1}, {0, -1}, {1, 0}, {-1, 0}};
        Queue<int[]> queue = new ArrayDeque<>();
        for (int i = 0; i < rows; i++) {
            for (int j = 0; j < cols; j++) {
                if (mat[i][j] == 0) {
                    queue.add(new int[]{i, j});
                } else {
                    mat[i][j] = Integer.MAX_VALUE;
                }
            }
        }
        while (!queue.isEmpty()) {
            int[] cell = queue.poll();
            int row = cell[0];
            int col = cell[1];
            for (int[] direction : directions) {
                int newRow = row + direction[0];
                int newCol = col + direction[1];
                if (newRow >= 0 && newRow < rows && newCol >= 0 && newCol < cols && mat[newRow][newCol] > mat[row][col] + 1) {
                    mat[newRow][newCol] = mat[row][col] + 1;
                    queue.add(new int[]{newRow, newCol});
                }
            }
        }
        return mat;        
    }
}Code language: PHP (php)

01 Matrix Leetcode Solution JavaScript

var updateMatrix = function(mat) {
    const rows = mat.length;
    const cols = mat[0].length;
    const directions = [[0, 1], [0, -1], [1, 0], [-1, 0]];
    const queue = [];
    for (let i = 0; i < rows; i++) {
        for (let j = 0; j < cols; j++) {
            if (mat[i][j] === 0) {
                queue.push([i, j]);
            } else {
                mat[i][j] = Infinity;
            }
        }
    }
    while (queue.length > 0) {
        const [row, col] = queue.shift();
        for (const [dr, dc] of directions) {
            const new_row = row + dr;
            const new_col = col + dc;
            if (new_row >= 0 && new_row < rows && new_col >= 0 && new_col < cols && mat[new_row][new_col] > mat[row][col] + 1) {
                mat[new_row][new_col] = mat[row][col] + 1;
                queue.push([new_row, new_col]);
            }
        }
    }
    return mat;    
};Code language: JavaScript (javascript)

01 Matrix Leetcode Solution Python

class Solution(object):
    def updateMatrix(self, mat):
        rows, cols = len(mat), len(mat[0])
        directions = [(0, 1), (0, -1), (1, 0), (-1, 0)]
        queue = deque()
        for i in range(rows):
            for j in range(cols):
                if mat[i][j] == 0:
                    queue.append((i, j))
                else:
                    mat[i][j] = float('inf')
        while queue:
            row, col = queue.popleft()
            for dr, dc in directions:
                new_row, new_col = row + dr, col + dc
                if 0 <= new_row < rows and 0 <= new_col < cols and mat[new_row][new_col] > mat[row][col] + 1:
                    mat[new_row][new_col] = mat[row][col] + 1
                    queue.append((new_row, new_col))
        return mat