# Definition for singly-linked list.
class ListNode(object):
def __init__(self, x):
self.val = x
self.next = None
class DoubleNode(object):
def __init__(self, key, val, pre=None, next=None):
self.key = key
self.val = val
self.pre = pre
self.next = next
# Definition for a binary tree node.
class TreeNode(object):
def __init__(self, x):
self.val = x
self.left = None
self.right = None
class TrieNode(object):
def __init__(self, end=False):
self.children = []
for i in range(26):
self.children.append(None)
self.end = end
def set_end(self):
self.end = True
@property
def is_end(self):
return self.end
class RandomNode(object):
def __init__(self, val, next, random):
self.val = val
self.next = next
self.random = random
class GraphNode(object):
def __init__(self, val, neighbors):
self.val = val
self.neighbors = neighbors
