Bricks Falling When Hit LeetCode solution in Java

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class Solution {
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  int[][] dirs = new int[][] {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
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  public int[] hitBricks(int[][] grid, int[][] hits) {
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    // marking all the hits that has a brick with -1
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    for (int i = 0; i < hits.length; i++)
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      if (grid[hits[i][0]][hits[i][1]] == 1) grid[hits[i][0]][hits[i][1]] = -1;
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    // marking all the stable bricks
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    for (int i = 0; i < grid[0].length; i++) markAndCountStableBricks(grid, 0, i);
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    int[] res = new int[hits.length];
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    // looping over hits array backwards and restoring bricks
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    for (int i = hits.length - 1; i >= 0; i--) {
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      int row = hits[i][0];
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      int col = hits[i][1];
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      // hit is at empty space so continue
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      if (grid[row][col] == 0) continue;
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      // marking it with 1, this signifies that a brick is present in an unstable state and will be
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      // restored in the future
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      grid[row][col] = 1;
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      // checking brick stability, if it's unstable no need to visit the neighbours
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      if (!isStable(grid, row, col)) continue;
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      // So now as our brick is stable we can restore all the bricks connected to it
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      // mark all the unstable bricks as stable and get the count
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      res[i] =
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          markAndCountStableBricks(grid, hits[i][0], hits[i][1])
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              - 1; // Subtracting 1 from the total count, as we don't wanna include the starting
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      // restored brick
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    }
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    return res;
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  }
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  private int markAndCountStableBricks(int[][] grid, int row, int col) {
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    if (grid[row][col] == 0 || grid[row][col] == -1) return 0;
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    grid[row][col] = 2;
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    int stableBricks = 1;
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    for (int[] dir : dirs) {
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      int r = row + dir[0];
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      int c = col + dir[1];
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      if (r < 0 || r >= grid.length || c < 0 || c >= grid[0].length) continue;
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      if (grid[r][c] == 0 || grid[r][c] == -1 || grid[r][c] == 2) continue;
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      stableBricks += markAndCountStableBricks(grid, r, c);
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    }
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    return stableBricks;
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  }
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  private boolean isStable(int[][] grid, int row, int col) {
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    if (row == 0) return true;
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    for (int[] dir : dirs) {
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      int r = row + dir[0];
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      int c = col + dir[1];
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      if (r < 0 || r >= grid.length || c < 0 || c >= grid[0].length) continue;
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      if (grid[r][c] == 2) return true;
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    }
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    return false;
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  }
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}