Given a n-ary tree, find its maximum depth.

maximum-depth-of-n-ary-tree.java

class Solution {
    public int maxDepth(Node root) {
        if (root == null) {
            return 0;
        }
        return dfs(root);
    }
    
    public int dfs(Node n) {
        int maxChild = 0;
        for (Node child : n.children) {
            int childDep = dfs(child);
            if (childDep > maxChild) {
                maxChild = childDep;
            }
        }
        maxChild++;
        return maxChild;
    }
}