[剑指Offer] 61.序列化二叉树

题目描述

请实现两个函数，分别用来序列化和反序列化二叉树

 /*
 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 == NULL)
         {
             return "#";
         }
         string cur_val = to_string(root->val);
         cur_val += '!';
         char* left = Serialize(root->left);
         char* right = Serialize(root->right);
         char* ret = new char[strlen(left) + strlen(right) + cur_val.size()];
         strcpy(ret, cur_val.c_str());
         strcat(ret, left);
         strcat(ret, right);
         return ret;
     }
     TreeNode* Deserialize(char* str)
     {
         return Decode(str);
     }
     TreeNode* Decode(char*& str)
     {
         if (*str == '#')
         {
             str ++;
             return NULL;
         }
         string val;
         while (*str != '!')
         {
             val += *str;
             ++str;
         }
         TreeNode* new_node = new TreeNode(stoi(val));
         ++str;
         new_node->left = Decode(str);
         new_node->right = Decode(str);

         return new_node;
     }
 };