2658. Maximum Number of Fish in a Grid

class Solution {
public:
    int findMaxFish(vector<vector<int>>& grid) {
        int m = grid.size(), n = grid[0].size();
        int maxFish = 0;
        for (int i = 0; i < m; i++) {
            for (int j = 0; j < n; j++) {
                if (grid[i][j] > 0) {
                    maxFish = max(maxFish, dfs(grid, i, j));
                }
            }
        }
        return maxFish;
    }
    int dfs(vector<vector<int>>& grid, int i, int j) {
        int m = grid.size(), n = grid[0].size();
        if (i < 0 || j < 0 || i >= m || j >= n || grid[i][j] == 0) {
            return 0;
        }
        int numberOfFish = grid[i][j];
        grid[i][j] = 0;

        vector<vector<int>> directions = {{0, -1}, {0, 1}, {1, 0}, {-1, 0}};
        for (const auto& dir : directions) {
            numberOfFish += dfs(grid, i + dir[0], j + dir[1]);
        }
        return numberOfFish;
    }
};