From a742225d4210bcc4d7aa1d654a0165ea59531585 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zeynep=20Nur=20Do=C4=9Faner?=
 <58522099+zndoganer@users.noreply.github.com>
Date: Sun, 30 Jul 2023 22:34:13 +0300
Subject: [PATCH] Segmentation Fault is Fixed

- "For loop" index limit made "n/2". This change avoids "temp" to accessing out of its boundary and prevents segmentation fault.
- Code is formatted.
---
 .../Serialize and Deserialize Binary Tree.cpp | 129 +++++++++---------
 1 file changed, 66 insertions(+), 63 deletions(-)

diff --git a/Trees/Serialize and Deserialize Binary Tree.cpp b/Trees/Serialize and Deserialize Binary Tree.cpp
index 201fc0f4..c61268ff 100644
--- a/Trees/Serialize and Deserialize Binary Tree.cpp	
+++ b/Trees/Serialize and Deserialize Binary Tree.cpp	
@@ -1,103 +1,106 @@
-#include<bits/stdc++.h>
+#include <bits/stdc++.h>
 using namespace std;
 
+// Definition for a binary tree node.
+struct TreeNode
+{
+    int val;
+    TreeNode *left;
+    TreeNode *right;
+    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
+};
 
- // Definition for a binary tree node.
-  struct TreeNode {
-     int val;
-     TreeNode *left;
-     TreeNode *right;
-     TreeNode(int x) : val(x), left(NULL), right(NULL) {}
-  };
- 
-class Codec {
+class Codec
+{
 public:
-
-    
-    string serialize(TreeNode* root) // Encodes a tree to a single string
+    string serialize(TreeNode *root) // Encodes a tree to a single string
     {
-       string s="";
-        if(root==NULL)//Wherever the root is NULL,simply add "X ";
+        string s = "";
+        if (root == NULL) // Wherever the root is NULL,simply add "X ";
             return "X ";
-        s+=(to_string(root->val)+" ");//Add the value string,then space and got to left and then right
-        s+=serialize(root->left);
-        s+=serialize(root->right);
+        s += (to_string(root->val) + " "); // Add the value string,then space and got to left and then right
+        s += serialize(root->left);
+        s += serialize(root->right);
         return s;
     }
 
-    
-    TreeNode* func(string data,int& ind)// Decodes your encoded data to tree.
+    TreeNode *func(string data, int &ind) // Decodes your encoded data to tree.
     {
-        if((data[ind]=='X')||(ind>=data.length()))//If the value at index is 'X',that implies the node was null
+        if ((data[ind] == 'X') || (ind >= data.length())) // If the value at index is 'X',that implies the node was null
         {
-            ind+=2;
+            ind += 2;
             return NULL;
         }
-        string sx="";
-        while((ind<data.length())&&(data[ind]!=' '))//To get the value at that node
+        string sx = "";
+        while ((ind < data.length()) && (data[ind] != ' ')) // To get the value at that node
         {
-            sx+=data[ind];
+            sx += data[ind];
             ind++;
         }
         ind++;
-        int temp1=stoi( sx );
-        TreeNode* nx=new TreeNode(temp1);//Add this node and process for left and right 
-        nx->left=func(data,ind);
-        nx->right=func(data,ind);
+        int temp1 = stoi(sx);
+        TreeNode *nx = new TreeNode(temp1); // Add this node and process for left and right
+        nx->left = func(data, ind);
+        nx->right = func(data, ind);
         return nx;
     }
-    
-    TreeNode* deserialize(string data) {
-        int ind=0;
-        return func(data,ind);//Calling the function with indices
+
+    TreeNode *deserialize(string data)
+    {
+        int ind = 0;
+        return func(data, ind); // Calling the function with indices
     }
-};//End of Codec Class
+}; // End of Codec Class
 
-void inorder(TreeNode* temp)//Inorder traversal of the tree
+void inorder(TreeNode *temp) // Inorder traversal of the tree
 {
-    if(temp==NULL)
-      return ;
+    if (temp == NULL)
+        return;
     inorder(temp->left);
-    cout<<temp->val<<" ";
+    cout << temp->val << " ";
     inorder(temp->right);
-    return ;
+    return;
 }
 
 int main()
 {
     int n;
-    cin>>n;//Number of nodes in full binary tree.
+    cin >> n; // Number of nodes in full binary tree.
+
     vector<int> v(n);
-    for(int i=0;i<n;i++)//Taking input of the tree as a level-order-vector and make it full binary tree by adding value -1 at null values
-      cin>>v[i];
-      vector<TreeNode* > temp(n);
-    for(int i=0;i<n;i++)//Creating the nodes
+    vector<TreeNode *> temp(n);
+
+    for (int i = 0; i < n; i++) // Taking input of the tree as a level-order-vector and make it full binary tree by adding value -1 at null values
+        cin >> v[i];
+
+    for (int i = 0; i < n; i++) // Creating the nodes
     {
-        if(v[i]==-1)
-          temp[i]=NULL;
+        if (v[i] == -1)
+            temp[i] = NULL;
         else
-         temp[i]=new TreeNode(v[i]);
+            temp[i] = new TreeNode(v[i]);
     }
-    for(int i=0;i<n;i++)//Creating the binary tree by adding links
+
+    for (int i = 0; i < n / 2; i++) // Creating the binary tree by adding links
     {
-        if(temp[i]!=NULL)
+        if (temp[i] != NULL)
         {
-            temp[i]->left=temp[2*i+1];
-            temp[i]->right=temp[2*i+2];
+            temp[i]->left = temp[2 * i + 1];
+            temp[i]->right = temp[2 * i + 2];
         }
     }
-    
-    Codec codec;//Object Creation
-    TreeNode* head=codec.deserialize(codec.serialize(temp[0]));//Passing temp[0] as root parameter
-      cout<<"Inorder Traversal is:"<<endl;
-      inorder(head);//Checking whether the process went correct by printing the values of the tree in inorder fashion
-     return 0;
-    
+
+    Codec codec;                                                  // Object Creation
+    TreeNode *head = codec.deserialize(codec.serialize(temp[0])); // Passing temp[0] as root parameter
+    cout << "Inorder Traversal is:" << endl;
+    inorder(head); // Checking whether the process went correct by printing the values of the tree in inorder fashion
+    return 0;
 }
 
-//Eg input :-
+// Tested with below example (Segmentation fault is fixed.)
+// Eg input :-
 // 15
-//1 2 3 -1 -1 5 4 -1 -1 -1 -1 -1 -1 -1 -1
-//Output:-
-//Inorder Traversal is:
-//2 1 5 3 4 
+// 1 2 3 -1 -1 5 4 -1 -1 -1 -1 -1 -1 -1 -1
+// Output:-
+// Inorder Traversal is:
+// 2 1 5 3 4