Binary Tree

binaryTree.cpp

#include <iostream>

using namespace std;

struct node {
    int key;
    int size;
    node *left;
    node *right;
    
    node(const int& _key) :
    key(_key), size(1), left(NULL), right(NULL) {}
    
    void setLeft(node* newNode) { left = newNode; calSize(); }
    void setRight(node* newNode) { right = newNode; calSize(); }
    
    void calSize() {
        size = 1;
        if (left) size += left->size;
        if (right) size += right->size;
    };
    
};

void inOrder(node *n) {
    if (n->left) {
        inOrder(n->left);
    }
    cout << n->key << endl;
    if (n->right) {
        inOrder(n->right);
    }
}

void preOrder(node *n) {
    cout << n->key << endl;
    if (n->left) {
        preOrder(n->left);
    }
    if (n->right) {
        preOrder(n->right);
    }
}

void postOrder(node *n) {
    if (n->left) {
        postOrder(n->left);
    }
    if (n->right) {
        postOrder(n->right);
    }
    cout << n->key << endl;
}

int main(int argc, const char * argv[]) {
    
    node *node5 = new node(5);
    node *node3 = new node(3);
    node *node1 = new node(1);
    
    node *node2 = new node(2);
    node2->setLeft(node1);
    node2->setRight(node3);
    
    node *node4 = new node(4);
    node4->setLeft(node2);
    node4->setRight(node5);
    
    cout << "InOrder" << endl;
    inOrder(node4);
    
    cout << "PreOrder" << endl;
    preOrder(node4);
    
    cout << "PostOrder" << endl;
    postOrder(node4);

    return 0;
}