297. Serialize and Deserialize Binary Tree

Author: amitbansal7

serialize-and-deserialize-binary-tree.cpp

@@ -0,0 +1,79 @@
+//Runtime: 29 ms
+class Codec {
+public:
+
+    // Encodes a tree to a single string.
+    string serialize(TreeNode* root) {
+        if(!root)
+            return "";
+        queue<TreeNode*> Q;
+        Q.push(root);
+        string s;
+        int len;
+        while(!Q.empty())
+        {
+            TreeNode* t = Q.front();
+            Q.pop();
+
+            if(t)
+            {
+                s += to_string(t->val) + ',';
+                len = s.size();
+            }
+
+            else
+                s += "#,";
+
+            if(t)
+            {
+                Q.push(t->left);
+                Q.push(t->right);
+            }
+        }
+        s = s.substr(0, len-1);
+        return s;
+    }
+
+    // Decodes your encoded data to tree.
+    TreeNode* deserialize(string data) {
+        vector<string> S;
+        if(data.size()<=0)
+            return NULL;
+
+        for(int i=0;i<data.size();i++)
+        {
+            string s;
+            while(i<data.size() && data[i] != ',')
+                s += data[i++];
+            S.push_back(s);
+        }
+        TreeNode* root;
+        int i = 0;
+        queue<TreeNode*> Q;
+        root = new TreeNode(stoi(S[i++]));
+        Q.push(root);
+        while(!Q.empty() && i<S.size())
+        {
+            TreeNode* t = Q.front();
+            Q.pop();
+
+            if(S[i] != "#")
+            {
+                t->left = new TreeNode(stoi(S[i++]));
+                Q.push(t->left);
+            }
+            else
+                i++;
+
+            if(i<S.size() && S[i] != "#")
+            {
+                t->right = new TreeNode(stoi(S[i++]));
+                Q.push(t->right);
+            }
+            else
+                i++;
+        }
+
+        return root;
+    }
+};