5.1.2二叉树的中序遍历

• • 1.题目
  • 2.代码

• 题目要求
• 思路
  二叉树的中序遍历顺序为左-根-右

class Solution{
public:
	vector result;
	vector inorderTraversal(TreeNode* root)
	{
		transefunction(root);
		return result;
	}
	
	void transefunction(TreeNode* node){
		if (!node)	return;
		transefunction(node->left);
		result.push_back(node->val);
		transefunction(node->right);
	}
};


class Solution{
public:
	vector inorderTraversal(TreeNode* root)
	{
		vector result;
		stack stack_treenode;
		TreeNode* p = root;
		while (!stack_treenode.empty() || p!=NULL)
		{
			if (!p)
			{
				stack_treenode.push(p);
				p=p->left;
			}
			else
			{
				TreeNode* top_node=stack_treenode.top();
				stack_treenode.pop();
				result.push_back(top_node->val);
				p=p->right;
			}
		}
		
		return result;
	}

};