leetcode-序列化二叉树-85

Posted 2022-03-19 天津 唐秙

题目要求

代码实现

/*
struct TreeNode 
    int val;
    struct TreeNode *left;
    struct TreeNode *right;
    TreeNode(int x) :
            val(x), left(NULL), right(NULL) 
    
;
*/
class Solution 
public:
    char* Serialize(TreeNode *root)     
        if(!root)
            return "#";
    
        string res = to_string(root->val);
        res.push_back(',');
    
        char* left = Serialize(root->left);
        char* right = Serialize(root->right);
    
        char* ret = new char[strlen(left) + strlen(right) + res.size()];
    
        strcpy(ret, res.c_str());
	    strcat(ret, left);
        strcat(ret, right);
    
        return ret;
    

    TreeNode* deseri(char *&s)
    
        if(*s == '#')
        
            s++;
            return nullptr;
        
    
        //构造根节点的值
        int num = 0;
        while(*s != ',')
        
            num = num * 10 + (*s - '0');
            s++;
        
        s++;
    
        //递归构造树
        TreeNode* root = new TreeNode(num);
        root->left = deseri(s);
        root->right = deseri(s);
    
        return root;
    
    
    TreeNode* Deserialize(char *str) 
        return deseri(str);
    
;