Merge pull request #1037 from bus710/week11

[bus710] Week 11

Author: TonyKim9401

maximum-depth-of-binary-tree/bus710.go

@@ -0,0 +1,28 @@
+package hello
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func maxDepth(root *TreeNode) int {
+	if root == nil {
+		return 0
+	}
+	return count(root)
+}
+
+func count(node *TreeNode) int {
+	if node == nil {
+		return 0
+	}
+
+	lc := count(node.Left) + 1
+	rc := count(node.Right) + 1
+
+	if lc > rc {
+		return lc
+	}
+	return rc
+}