Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
Note: A leaf is a node with no children.
Example:
Given binary tree [3,9,20,null,null,15,7],
3
/
9 20
/
15 7
return its depth = 3.
1 public int maxDepth(TreeNode root) {//树 递归 my 2 if(null==root){ 3 return 0; 4 } 5 int ld=maxDepth(root.left); 6 int lr = maxDepth(root.right); 7 int d = ld>lr?(ld+1):(lr+1); 8 return d; 9 }
还可以使用BFS
相关题
二叉树的最小深度 LeetCode111 https://www.cnblogs.com/zhacai/p/10598843.html