cringeTrees

#include <iostream>

using namespace std;

struct TreeNode {
    int data;
    TreeNode *left;
    TreeNode *right;
};

TreeNode *root1 = NULL, *root2 = NULL;

void buildTree(); // Функция постройки дерева
void initCopyTree();
void insertFromChild(TreeNode*, int);
void insertFromRoot(int);
void destroyTree(TreeNode*);
void preorderPrint(TreeNode*);
void copyTree(TreeNode*, TreeNode*);

int main() {
    setlocale(LC_ALL, "rus");

    buildTree();

    initCopyTree();
    preorderPrint(root2);


    destroyTree(root2);
    destroyTree(root1);
    return 0;
}

void insertFromChild(TreeNode *leaf, int key) {
    if (key < leaf->data) {
        if (leaf->left != NULL)
            insertFromChild(leaf->left, key);
        else {
            leaf->left = new TreeNode;
            leaf->left->data = key;
            leaf->left->left = NULL;
            leaf->left->right = NULL;
        }
    }
    else {
        if (leaf->right != NULL)
            insertFromChild(leaf->right, key);
        else {
            leaf->right = new TreeNode;
            leaf->right->data = key;
            leaf->right->left = NULL;
            leaf->right->right = NULL;
        }
    }
}

void insertFromRoot(int key) {
    if (root1 != NULL) {
        insertFromChild(root1, key);
    }
    else {
        root1 = new TreeNode;
        root1->data = key;
        root1->left = NULL;
        root1->right = NULL;
    }
}

void buildTree() {
    int n;
    cout << "Enter count of elements to insert in bintree:\n";
    cin >> n;
    cout << "Input elements:\n";
    for (int i = 0; i < n; i++) {
        int req;
        cin >> req;
        insertFromRoot(req);
    }
}

void destroyTree(TreeNode *leaf) {
    if (leaf != NULL) {
        destroyTree(leaf->left);
        destroyTree(leaf->right);
        delete leaf;
    }
}

void preorderPrint(TreeNode *root) {
    if (root == NULL) {
        return;
    }
    cout << root->data << ' ';
    preorderPrint(root->left);
    preorderPrint(root->right);
}

void initCopyTree() {
    if (root1 != NULL && root2 == NULL) {
        root2 = new TreeNode;
        root2->data = root1->data;
        root2->left = NULL;
        root2->right = NULL;
        copyTree(root1, root2);
    }
}

void copyTree(TreeNode *rootFrom, TreeNode *rootTo) {
    if (rootFrom->left != NULL) {
        rootTo->left = new TreeNode;
        rootTo->left->data = rootFrom->left->data;
        rootTo->left->left = NULL;
        rootTo->left->right = NULL;
        copyTree(rootFrom->left, rootTo->left);
    }
    else {
        rootTo->left = NULL;
    }

    if (rootFrom->right != NULL) {
        rootTo->right = new TreeNode;
        rootTo->right->data = rootFrom->right->data;
        rootTo->right->left = NULL;
        rootTo->right->right = NULL;
        copyTree(rootFrom->right, rootTo->right);
    }
    else {
        rootTo->right = NULL;
    }
}