public class LeetCode0104 {

	class TreeNode {
		int val;
		TreeNode left;
		TreeNode right;

		TreeNode(int x) {
			val = x;
		}
	}

	public int maxDepth(TreeNode root) {
		if (root == null) {
			return 0;
		}
		return 1 + Math.max(maxDepth(root.left), maxDepth(root.right));
	}
}
Add LeetCode0104.java