小黑准备下午去面试，希望经过了之前的不幸这次能够幸运一些，虽然经历了一些恶心的事情还是要相信世界的美好的leetcode之旅:111. 二叉树的最小深度

小黑代码

# Definition for a binary tree node. # class TreeNode: # def __init__(self, val=0, left=None, right=None): # self.val = val # self.left = left # self.right = right class Solution: def minDepth(self, root: Optional[TreeNode]) -> int: if not root: return 0 depth = 0 # 初始化队列 q = collections.deque([root]) # 层次便利 while q: depth += 1 # 记录该层有多少元素 n = len(q) # 遍历每一个结点 for _ in range(n): top = q.popleft() if top.left: q.append(top.left) if top.right: q.append(top.right) # 叶子结点 if not (top.left or top.right): return depth return -1

深度优先

# Definition for a binary tree node. # class TreeNode: # def __init__(self, val=0, left=None, right=None): # self.val = val # self.left = left # self.right = right class Solution: def minDepth(self, root: Optional[TreeNode]) -> int: if not root: return 0 if not (root.left or root.right): return 1 min_depth = float('inf') # 取左右子树最小值 if root.left: min_depth = min(min_depth, self.minDepth(root.left)) if root.right: min_depth = min(min_depth, self.minDepth(root.right)) return min_depth + 1

层次便利

# Definition for a binary tree node. # class TreeNode: # def __init__(self, val=0, left=None, right=None): # self.val = val # self.left = left # self.right = right class Solution: def minDepth(self, root: Optional[TreeNode]) -> int: if not root: return 0 # 初始化队列,记录深度 q = collections.deque([(root, 1)]) # 层次遍历 while q: top = q.popleft() node, depth = top if node.left: q.append((node.left, depth + 1)) if node.right: q.append((node.right, depth + 1)) # 发现最浅叶子结点 if not (node.left or node.right): return depth return -1

小黑生活

被阿黄放了鸽子啦，真是个好男人

从家骑到朝阳公园准备享受一番

跟justRUN一起慢跑享受

生活要有仪式感，来杯喜茶

半小时从朝阳公园小黄车狂飙到垂杨柳宇飞，赶在关门前一分钟吃到了牛肉面

一会儿买杯喜茶，下午面试加油，面完试跟尚香疯狂星期四！！！！