c/c++ linked list and binary tree examples. node addition and traversing

main.cpp

#include <iostream>

using namespace std;


/**
 * Tek yonlu liste tanimi
 */
struct Node {
  int data;
  struct Node *next;
};


/**
 * Ikili agac tanimi, yeni eleman veriden
 * buyukse saga, kucukse sola eklenecek
 */
struct TreeNode {
  int data;
  struct TreeNode *left;
  struct TreeNode *right;
};


void printlist(struct Node *head) {
    uint rank = 1;
    struct Node *temp = head;
    if (head) {
        cout << rank << " : " << temp->data << endl;
    }
    while (temp->next != nullptr) {
        rank++;
        temp = temp->next;
        cout << rank << " : " << temp->data << endl;

    }
}

void add_node(int data, Node *head) {
    struct Node *temp = head;
    while (temp->next != nullptr) {
        temp = temp->next;
    }
    struct Node *newnode = nullptr;
    newnode = (Node *)malloc(sizeof(Node));
    newnode->data = data;
    newnode->next = nullptr;
    temp->next = newnode;
}


/**
 * recursive node ekleme.
 * verilen sayiyi node icindeki sayi ile karsilastirir
 * kucukse sola, buyukse saga gidecek sekilde kendisini cagirir
 * sol ya da sagda gidecek dal kalmadiginda, orada yeni node olusturur
 */
TreeNode* add_treenode(int data, TreeNode *head) {
    if(head == nullptr) {
        head = (TreeNode *)malloc(sizeof(TreeNode));
        head->data = data;
        head->left = nullptr;
        head->right = nullptr;
        return head;
    }

    if (data < head->data) {
        head->left = add_treenode(data, head->left);
    }
    else {
        head->right = add_treenode(data, head->right);
    }
    return head;
}

void traverse(TreeNode *head, int order) { // 0 ascending, 1 descending
    if (head == nullptr) return;

    if (order == 0)
    {
        traverse(head->left, order);
        cout << head->data << " ";
        traverse(head->right, order);
    }
    else if (order == 1) {
        traverse(head->right, order);
        cout << head->data << " ";
        traverse(head->left, order);
    }
}


int main()
{
    struct Node *head = nullptr;
    struct Node *newnode = nullptr;
    head = (Node *)malloc(sizeof(Node));
    head->data = 1;
    head->next = nullptr;

    add_node(2, head);
    add_node(4, head);
    add_node(6, head);
    add_node(8, head);
    add_node(11, head);
    add_node(3, head);
    //printlist(head);

    struct TreeNode *treehead = nullptr;
    treehead = add_treenode(500, treehead);
    add_treenode(350, treehead);
    add_treenode(550, treehead);
    add_treenode(2345, treehead);
    add_treenode(32, treehead);
    add_treenode(10, treehead);
    add_treenode(3150, treehead);
    add_treenode(3530, treehead);
    add_treenode(12, treehead);
    add_treenode(124, treehead);
    add_treenode(1, treehead);
    add_treenode(2, treehead);
    add_treenode(122350, treehead);
    traverse(treehead,1);
    cout << endl;
    traverse(treehead,0);
    cout << endl;
    return 0;
}