tree

#include <stdio.h>
#include <stdlib.h>

struct Node {
    int data;
    struct Node *left, *right;
};

struct Node *newNode(int data) {
    struct Node *node = (struct Node *)malloc(sizeof(struct Node));
    node->data = data;
    node->left = node->right = NULL;
    return node;
}

void printPostorder(struct Node *node) {
    if (node == NULL)
        return;
    printPostorder(node->left);
    printPostorder(node->right);
    printf("%d ", node->data);
}

void printInorder(struct Node *node) {
    if (node == NULL)
        return;
    printInorder(node->left);
    printf("%d ", node->data);
    printInorder(node->right);
}

void printPreorder(struct Node *node) {
    if (node == NULL)
        return;
    printf("%d ", node->data);
    printPreorder(node->left);
    printPreorder(node->right);
}

int main() {
    struct Node *root = newNode(1);
    root->left = newNode(2);
    root->right = newNode(3);
    root->left->left = newNode(4);
    root->left->right = newNode(5);

    printf("\nPreorder traversal: ");
    printPreorder(root);
    printf("\nInorder traversal: ");
    printInorder(root);
    printf("\nPostorder traversal: ");
    printPostorder(root);

    getchar();
    return 0;
}