二叉树中序遍历递归实现

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func inorderTraversal(root *TreeNode) []int {
    rsp := make([]int, 0)
    if nil == root {
        return rsp
    }

    rsp = append(rsp,inorderTraversal(root.Left)...)
    rsp = append(rsp, root.Val)
    rsp = append(rsp,inorderTraversal(root.Right)...)
    return rsp
}