LC 0117 [M] Populating Next Right Pointers in Each Node II - ALawliet/algorithms GitHub Wiki
"""
# Definition for a Node.
class Node:
def __init__(self, val: int = 0, left: 'Node' = None, right: 'Node' = None, next: 'Node' = None):
self.val = val
self.left = left
self.right = right
self.next = next
"""
class Solution:
def connect(self, root: 'Node') -> 'Node':
if not root:
return root
Q = deque([root])
while Q:
prev = None
for _ in range(len(Q)):
node = Q.popleft()
if prev:
prev.next = node
prev = node
if node.left:
Q.append(node.left)
if node.right:
Q.append(node.right)
return root