Flood Fill

 

package pep.Day11;

public class FloodFill {
    public static void main(String[] args) {
        int[][] arr = new int[][]{
                {0, 0, 0},
                {1, 0, 0},
                {0, 0, 0}
        };

        boolean[][] visited = new boolean[arr.length][arr[0].length];
        floodfill(arr, 0, 0, "", visited);
    }

    private static void floodfill(int[][] arr, int row, int col, String ans, boolean[][] visited) {
        if (row == arr.length - 1 && col == arr[0].length - 1) {
            System.out.println(ans);
            return;
        }

        if (row < 0 || col < 0 || row > arr.length - 1 || col > arr[0].length - 1 || arr[row][col] == 1 || visited[row][col] == true) {
            return;
        }
        visited[row][col] = true;
        floodfill(arr, row - 1, col, ans + "t", visited);
        floodfill(arr, row, col - 1, ans + "l", visited);
        floodfill(arr, row + 1, col, ans + "d", visited);
        floodfill(arr, row, col + 1, ans + "r", visited);
        visited[row][col] = false;


    }
}

package pep.Day11;

import static PRACTICE.Recursion.BackTracking.FloodFill.floodfill_method1;

public class FloodFill {
    public static void main(String[] args) {
        int[][] arr = new int[][]{
                {0, 0, 0},
                {1, 0, 0},
                {0, 0, 0}
        };

        boolean[][] visited = new boolean[arr.length][arr[0].length];
        floodfill_method1(arr, 0, 0, "", visited);
    }

    private static void floodfill_method1(int[][] maze, int row, int col, String ans, boolean[][] visited) {
        if (row == maze.length - 1 && col == maze[0].length - 1) {
            System.out.println(ans);
            return;
        }

        if (row < 0 || col < 0 || row > maze.length - 1 || col > maze[0].length - 1 || maze[row][col] == 1 || visited[row][col] == true) {
            return;
        }
        visited[row][col] = true;

        floodfill_method1(maze, row - 1, col, ans + "t", visited);
        floodfill_method1(maze, row, col - 1, ans + "l", visited);
        floodfill_method1(maze, row + 1, col, ans + "d", visited);
        floodfill_method1(maze, row, col + 1, ans + "r", visited);
        visited[row][col] = false;


    }


    private static void floodfill_method2(int[][] maze, int row, int col, String ans, boolean[][] visited) {
        if (row == maze.length - 1 && col == maze[0].length - 1) {
            System.out.println(ans);
            return;
        }

        if (row < 0 || col < 0 || row > maze.length - 1 || col > maze[0].length - 1 || maze[row][col] == 1 || visited[row][col] == true) {
            return;
        }
        visited[row][col] = true;


        int[][] arr = {{-1, 0}, {0, -1}, {1, 0}, {0, 1}};
        String[] dir = new String[]{"t", "l", "d", "r"};

        for (int i = 0; i < arr.length; i++)
            floodfill_method2(maze, row + arr[i][0], col + arr[i][1], ans + dir[i], visited);

        visited[row][col] = false;


    }


}