高度最小的BST

class MinimalBST:
    def buildMinimalBST(self, vals):
        # write code here
        if not vals:
            return 0
        mid = int(len(vals) / 2)
        return max(self.buildMinimalBST(vals[:mid]), self.buildMinimalBST(vals[mid + 1:])) + 1

python solution

class MinimalBST:
    def buildMinimalBST(self, vals):
        res=0
        while 2**res<len(vals):
            res+=1
        return res

# -*- coding:utf-8 -*-
class MinimalBST:
    def buildMinimalBST(self, vals):
        # write code here
        if len(vals)<=0:
            return None
        root = self.buildBST(vals,0,len(vals)-1)
        height = self.getHeight(root)
        return height
    
    def buildBST(self,vals,left,right):
        if left>right:
            return None
        mid = (left + right)/2
        root = TreeNode(vals[mid])
        root.left = self.buildBST(vals,left,mid-1)
        root.right = self.buildBST(vals,mid+1,right)
        return root
    
    def getHeight(self, root):
        if root is None:
            return 0
        if self.getHeight(root.left)>self.getHeight(root.right):
            return self.getHeight(root.left)+1
        else:
            return self.getHeight(root.right)+1
    

# -*- coding:utf-8 -*-
class MinimalBST:
    def buildMinimalBST(self, vals):
        import math
        return int(math.log(len(vals), 2)) + 1