Method dfs

maximumNumberOfFishesInAGrid.java:18–30

(int r, int c, int grid[][])

        return maxFishes;
    }
    public int dfs(int r, int c, int grid[][]){
        //base case
        //out of the matrix
        //land cell -> 0
        //visited ->0
        if(r<0 || r>=rows || c<0 || c>= cols || grid[r][c] == 0){
            return 0;
        }
        int ans = grid[r][c];
        grid[r][c] = 0;
        ans += dfs(r-1,c,grid) + dfs(r,c+1,grid) + dfs(r+1,c,grid) + dfs(r,c-1,grid);
        return ans;
    }
}