src/main/java/com/fishercoder/solutions/_1110.java

package com.fishercoder.solutions;

import com.fishercoder.common.classes.TreeNode;

import java.util.ArrayList;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;

public class _1110 {
    public static class Solution1 {
        public List<TreeNode> delNodes(TreeNode root, int[] toDelete) {
            Queue<TreeNode> queue = new LinkedList<>();
            queue.offer(root);
            for (int d : toDelete) {
                delete(d, queue);
            }
            List<TreeNode> result = new ArrayList<>();
            while (!queue.isEmpty()) {
                result.add(queue.poll());
            }
            return result;
        }

        private void delete(int toDelete, Queue<TreeNode> queue) {
            int size = queue.size();
            for (int i = 0; i < size; i++) {
                TreeNode curr = queue.poll();
                if (delete(curr, toDelete, queue)) {
                    if (toDelete != curr.val) {
                        queue.offer(curr);
                    }
                    break;
                } else {
                    queue.offer(curr);
                }
            }
        }

        private boolean delete(TreeNode curr, int toDelete, Queue<TreeNode> queue) {
            if (curr == null) {
                return false;
            } else {
                if (curr.val == toDelete) {
                    if (curr.left != null) {
                        queue.offer(curr.left);
                    }
                    if (curr.right != null) {
                        queue.offer(curr.right);
                    }
                    return true;
                } else if (curr.left != null && curr.left.val == toDelete) {
                    if (curr.left.left != null) {
                        queue.offer(curr.left.left);
                    }
                    if (curr.left.right != null) {
                        queue.offer(curr.left.right);
                    }
                    curr.left = null;
                    return true;
                } else if (curr.right != null && curr.right.val == toDelete) {
                    if (curr.right.left != null) {
                        queue.offer(curr.right.left);
                    }
                    if (curr.right.right != null) {
                        queue.offer(curr.right.right);
                    }
                    curr.right = null;
                    return true;
                }
                return delete(curr.left, toDelete, queue) || delete(curr.right, toDelete, queue);
            }
        }
    }
}