【牛客网】二叉搜索树与双向链表

链接: 二叉搜索树与双向链表

题目描述

算法分析

编程代码

/*
struct TreeNode {
	int val;
	struct TreeNode *left;
	struct TreeNode *right;
	TreeNode(int x) :
			val(x), left(NULL), right(NULL) {
	}
};*/
class Solution {
public:

	void InOrder(TreeNode* root,TreeNode*& pre){
		if(root == nullptr)
		{
			return;
		}

		InOrder(root->left,pre);
		root->left = pre;
		if(pre)
		{
			pre->right = root;
		}
		pre = root;
		InOrder(root->right,pre);
	}

    TreeNode* Convert(TreeNode* pRootOfTree) {
		if(pRootOfTree == nullptr)
		{
			return pRootOfTree;
		}
		TreeNode* pre = nullptr;
        InOrder(pRootOfTree,pre);
		while(pRootOfTree->left)
		{
			pRootOfTree = pRootOfTree->left;
		}
		return pRootOfTree;
    }
};