Function buildTree

leetcode/main.go:511–526

LC 106 从中序与后序遍历序列构造二叉树

(inorder []int, postorder []int)

// LC 106 从中序与后序遍历序列构造二叉树
func buildTree(inorder []int, postorder []int) *TreeNode {
    if len(inorder) == 0 {
        return nil
    }
    rootVal := postorder[len(postorder)-1]
    for i, v := range inorder {
        if v == rootVal {
            return &TreeNode{
                rootVal,
                buildTree(inorder[:i], postorder[:i]),
                buildTree(inorder[i+1:], postorder[i:len(postorder)-1]),
            }
        }
    }
    panic(1)
}

// LC 117, O(1) 空间复杂度
func connect(root *Node) *Node {