I have been having some difficulty with implementing a program that makes a LCRS Binary Tree from the users input. I need to have the program implement insertion, search, height, and preorder. So far I have gotten the insertion part to work, or at least it doesn't crash when inserting values . The problem is with my search function, it works if the value I'm looking for is the root node, but if it's deeper in the tree, it keeps returning false, earlier I was getting Access Errors, but I seemed to have resolved that bug. If anyone sees the error in my function, I would greatly appreciate the help. Thanks!

[functions]
Code:
  1. #include "BST.h"
  2. #include <cstdlib>
  3. #include <iostream>
  4. using namespace std;
  5. int Tree::command(string s) {
  6.     if (s == "insert") return 1;
  7.     if (s == "search") return 2;
  8.     if (s == "preorder") return 3;
  9.     if (s == "height") return 4;
  10.     if (s == "quit") return 5;
  11.     return -1;
  12. }
  13. bool Tree::insert(int value) {
  14.     if (root == NULL) {
  15.         root = new Node(value);
  16.         cout<<"Root: "<<root->value<<endl;
  17.         return true;
  18.     } else
  19.         return root->insert(value);
  20. }
  21. bool Node::insert(int value) {
  22.     if (value = this->value) return true;
  23.     else {
  24.         if (this->child == NULL) {
  25.             this->child = new Node(value);
  26.             return true;
  27.         } else {
  28.             if (value < this->value) {
  29.                 if (this->value < this->child->value && this->child->sibling == NULL) {
  30.                     Node *s = new Node(value);
  31.                     s->sibling = this->child;
  32.                     this->child = s;
  33.                     return true;
  34.                 }
  35.                 if (this->value > this->child->value && this->child->sibling == NULL)
  36.                     return this->child->insert(value);
  37.                 if (this->child->sibling != NULL)
  38.                     return this->child->insert(value);
  39.             }
  40.             if (value > this->value) {
  41.                 if (this->value < this->child->value && this->child->sibling == NULL) {
  42.                     return this->child->insert(value);
  43.                 }
  44.                 if (this->value > this->child->value && this->child->sibling == NULL) {
  45.                     this->child->sibling = new Node(value);
  46.                     return true;
  47.                 }
  48.                 if (this->child->sibling != NULL) {
  49.                     return this->child->sibling->insert(value);
  50.                 }
  51.             }
  52.         }
  53.     }
  54. }
  55. bool Tree::search(int value) {
  56.     if (root == NULL)
  57.     {
  58.         cout<<"is null"<<endl;
  59.         return false;
  60.     }
  61.     else{
  62.         if(root->value == value) return true;
  63.         else
  64.            return root->search(value);
  65.     }
  66. }
  67. bool Node::search(int value)
  68. {
  69.     if (this->value == value) return true;
  70.     else
  71.     {
  72.         if(this->child != NULL || this->sibling != NULL)
  73.         {
  74.         if(value > this->value && this->sibling != NULL)
  75.             return this->sibling->search(value);
  76.         if(value > this->value && this->sibling == NULL)
  77.             return false;
  78.         if(value < this->value && this->child != NULL)
  79.             return this->child->search(value);
  80.         if(value < this->value && this->child == NULL)
  81.             return false;
  82.         }
  83.         else return false;
  84.     }
  85. }
[header]
Code:
  1. #include <cstdlib>
  2. #include <string>
  3. using namespace std;
  4. class Node {
  5. public:
  6.     int value;
  7.     Node* child;
  8.     Node* sibling;
  9.     Node(int value) {
  10.         this->value = value;
  11.         child = NULL;
  12.         sibling = NULL;
  13.     }
  14.     bool insert(int );
  15.     bool search(int);
  16. };
  17. class Tree {
  18. private:
  19.     Node* root;
  20. public:
  21.     Tree() {
  22.         root = NULL;
  23.     }
  24.     bool insert(int );
  25.     int height(Tree *);
  26.     bool search(int );
  27.     void preorder(Tree *);
  28.     int command(string);
  29. };