559. N 叉树的最大深度

  1. /*
  2. // Definition for a Node.
  3. class Node {
  4.     public int val;
  5.     public List<Node> children;
  7.     public Node() {}
  9.     public Node(int _val) {
  10.         val = _val;
  11.     }
  13.     public Node(int _val, List<Node> _children) {
  14.         val = _val;
  15.         children = _children;
  16.     }
  17. };
  18. */
  20. class Solution {
  21.     public int maxDepth(Node root) {
  22.         if (root == null)
  23.             return 0;
  24.         else if (root.children.isEmpty())
  25.             return 1;
  27.         int maxDepth = 0;
  28.         for (Node child : root.children)  
  29.             maxDepth = Math.max(maxDepth, maxDepth(child));
  31.         return maxDepth + 1;
  33.     }
  34. }