二叉树的非递归遍历

先是中序遍历

/**
 * Definition for binary tree
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
 * };
 */
class Solution {
public:
    vector<int> inorderTraversal(TreeNode *root) {
        vector<int>v;
        stack<TreeNode*>s;
        TreeNode* p = root;
        while(!s.empty() || p != NULL){
            if(p != NULL){
                s.push(p);
                p = p->left;
            }else {
                p = s.top();
                s.pop();
                v.push_back(p->val);
                p = p->right;
            }
        } 
        return v;
    }
};

二叉树的非递归遍历

原文：http://blog.csdn.net/sina012345/article/details/42979843