C++ 解法, 执行用时: 2ms, 内存消耗: 344KB, 提交时间: 2020-12-20

class Solution {
  public:
    /**
     *
     * @param root TreeNode类 the root
     * @return int整型vector
     */
    vector<int> findError(TreeNode *root) {
        // write code herev
        vector<int> res, tmp;

        dfs(root, res);

        for (int i = 0; i < res.size() - 1; i++) {
            if (res[i] > res[i + 1]) {
                tmp.push_back(res[i]);
                int j = i + 1;
                while (j < res.size() && res[j] < res[i])
                    j++;
                tmp.push_back(res[j-1]);
                break;
            }
        }
        sort(tmp.begin(), tmp.end());
        return tmp;
    }
    void dfs(TreeNode *root, vector<int> &v) {
        if (root == nullptr)
            return;

        dfs(root->left, v);
        v.push_back(root->val);
        dfs(root->right, v);
    }
};

C++ 解法, 执行用时: 2ms, 内存消耗: 348KB, 提交时间: 2021-05-31

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 the root
     * @return int整型vector
     */
    vector<int> findError(TreeNode* root) {
        // write code here
        vector<int> v;
        if(!root) return v;
        stack<TreeNode*> s;
        int prev = INT_MIN, nei;
        TreeNode* n = root;
        while(!s.empty() || n){
            while(n){
                s.push(n);
                n = n->left;
            }
            n = s.top();
            s.pop();
            if(n->val < prev){
                if(v.size() == 0) {
                    v.push_back(prev);
                    nei = n->val;
                }
                else v.push_back(n->val);
            }
            prev = n->val;
            n = n->right;
        }
        if(v.size() == 1) v.push_back(nei);
        return vector<int>(v.rbegin(), v.rend());
    }
};

C++ 解法, 执行用时: 2ms, 内存消耗: 348KB, 提交时间: 2021-04-25

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 the root
     * @return int整型vector
     */
    int cur = INT_MIN;
    vector<int> findError(TreeNode* root) {
        // write code here
        vector<int> res(2);
        find(root, res);
        return res;
    }
    
    void find(TreeNode* root, vector<int>& res) {
        if(!root) return;
        
        find(root->left, res);
        if(cur > root->val) {
            res[0] = root->val;
            res[1] = cur;
        } else {
            cur = root->val;
        }
        
        find(root->right, res);
    }
};

C++ 解法, 执行用时: 2ms, 内存消耗: 348KB, 提交时间: 2021-01-31

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 the root
     * @return int整型vector
     */
    vector<int> findError(TreeNode* root) {
        // write code here
        vector<int>result;
        if(root==nullptr)
            return result;
        result.resize(2);
        TreeNode* cur=root;
        stack<TreeNode*>nodes;
        vector<int>nums;
        while(nodes.size()||cur)
        {
            if(cur)
            {
                nodes.push(cur);
                cur=cur->left;
               
            }else
            {
                cur=nodes.top();
                nodes.pop();
                nums.push_back(cur->val);
                cur = cur->right;
            }
        }
        
        for(int i=0;i<nums.size()-1;++i)
            if(nums[i]>nums[i+1])
            {
                result[1]=nums[i];
                break;
            }
        for(int i=nums.size()-1;i>0;--i)
            if(nums[i]<nums[i-1])
            {
                result[0]=nums[i];
                 break;
            }
        return result;
    }
};

C++ 解法, 执行用时: 2ms, 内存消耗: 356KB, 提交时间: 2021-05-09

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 * };
 */

class Solution {
public:
    /**
     * 
     * @param root TreeNode类 the root
     * @return int整型vector
     */
    vector<int> vec;
    TreeNode* pre=nullptr;
    int index=1;
    void inOrder(TreeNode* root){
        if(root==nullptr)
            return;
        inOrder(root->left);
        if(pre!=nullptr){
            if(index==1&&root->val<pre->val){  //找第一个数 要判断其小于之前的数 存pre
                vec[index]=pre->val;
                index--;
            }
            if(index==0&&root->val<pre->val)
                vec[index]=root->val;
        }
        pre=root;//初始指向第一个
        inOrder(root->right);
        
    }
    vector<int> findError(TreeNode* root) {
        // write code here
        vec.resize(2);
        if(root==nullptr)
            return vec;
        inOrder(root);
        return vec;
    }
};