• Time:O(mn)
• Space:O(mn)

## C++

``````class Solution {
public:
vector<vector<char>> updateBoard(vector<vector<char>>& board,
vector<int>& click) {
if (board[click[0]][click[1]] == 'M') {
board[click[0]][click[1]] = 'X';
return board;
}

dfs(board, click[0], click[1]);

return board;
}

private:
const vector<pair<int, int>> dirs{{-1, -1}, {-1, 0}, {-1, 1}, {0, -1},
{0, 1},   {1, -1}, {1, 0},  {1, 1}};

void dfs(vector<vector<char>>& board, int i, int j) {
if (i < 0 || i == board.size() || j < 0 || j == board[0].size())
return;
if (board[i][j] != 'E')
return;

const int minesCount = getMinesCount(board, i, j);
board[i][j] = minesCount == 0 ? 'B' : '0' + minesCount;

if (minesCount == 0)
for (const auto& [dx, dy] : dirs)
dfs(board, i + dx, j + dy);
}

int getMinesCount(const vector<vector<char>>& board, int i, int j) {
int minesCount = 0;
for (const auto& [dx, dy] : dirs) {
const int x = i + dx;
const int y = j + dy;
if (x < 0 || x == board.size() || y < 0 || y == board[0].size())
continue;
if (board[x][y] == 'M')
++minesCount;
}
return minesCount;
}
};
``````

## JAVA

``````class Solution {
public char[][] updateBoard(char[][] board, int[] click) {
if (board[click[0]][click[1]] == 'M') {
board[click[0]][click[1]] = 'X';
return board;
}

dfs(board, click[0], click[1]);

return board;
}

private static final int[][] dirs = {{-1, -1}, {-1, 0}, {-1, 1}, {0, -1},
{0, 1},   {1, -1}, {1, 0},  {1, 1}};

private void dfs(char[][] board, int i, int j) {
if (i < 0 || i == board.length || j < 0 || j == board[0].length)
return;
if (board[i][j] != 'E')
return;

final int minesCount = getMinesCount(board, i, j);
board[i][j] = minesCount == 0 ? 'B' : (char) ('0' + minesCount);

if (minesCount == 0)
for (int[] dir : dirs)
dfs(board, i + dir[0], j + dir[1]);
}

private int getMinesCount(char[][] board, int i, int j) {
int minesCount = 0;
for (final int[] dir : dirs) {
final int x = i + dir[0];
final int y = j + dir[1];
if (x < 0 || x == board.length || y < 0 || y == board[0].length)
continue;
if (board[x][y] == 'M')
++minesCount;
}
return minesCount;
}
}
``````

## Python

``````class Solution:
def updateBoard(self, board: List[List[str]], click: List[int]) -> List[List[str]]:
if board[click[0]][click[1]] == 'M':
board[click[0]][click[1]] = 'X'
return board

dirs = [(-1, -1), (-1, 0), (-1, 1), (0, -1),
(0, 1), (1, -1), (1, 0), (1, 1)]

def getMinesCount(i: int, j: int) -> int:
minesCount = 0
for dx, dy in dirs:
x = i + dx
y = j + dy
if x < 0 or x == len(board) or y < 0 or y == len(board[0]):
continue
if board[x][y] == 'M':
minesCount += 1
return minesCount

def dfs(i: int, j: int) -> None:
if i < 0 or i == len(board) or j < 0 or j == len(board[0]):
return
if board[i][j] != 'E':
return

minesCount = getMinesCount(i, j)
board[i][j] = 'B' if minesCount == 0 else str(minesCount)

if minesCount == 0:
for dx, dy in dirs:
dfs(i + dx, j + dy)

dfs(click[0], click[1])

return board
``````