July9_2020.java

// Max width of binary tree - level order traversal woth hack



class Solution {
    public int widthOfBinaryTree(TreeNode root) 
    {
		 if (root == null) {
            return 0;
        }
        Queue<TreeNode> queue = new LinkedList<>();
        int max = 1, leftmost = 1, rightmost = 1;
        root.val = 1;
        queue.offer(root);
        while (!queue.isEmpty()) {
            int size = queue.size();
            for (int i = 0; i < size; i++) {
                TreeNode cur = queue.poll();
                if (i == 0) {
                    leftmost = cur.val;
                }
                if (i == size - 1) {
                    rightmost = cur.val;
                }
                if (cur.left != null) {
                    cur.left.val = cur.val * 2;
                    queue.offer(cur.left);
                }
                if (cur.right != null) {
                    cur.right.val = cur.val * 2 + 1;
                    queue.offer(cur.right);
                }
            }
            max = Math.max(max, rightmost - leftmost + 1);

        }
        return max;
	}
}