TreeDataStructure

// Trees.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <iostream>
#include <fstream>
using namespace std;

struct tnode {
	int val;
	tnode *lchild;
	tnode *rchild;
};

tnode *root; //first node in a tree, similar to head of a linked list

tnode *myNewNode()
{
	tnode *t;
	t = new tnode;
	t->lchild = NULL;
	t->rchild = NULL;
	return t;
}


void insert(tnode* c, int target)
{
	//we need to have another pointer, a previous pointer, to keep track of the parent
	tnode *p; //previous pointer
	p = NULL;

	while (c)
	{
		p = c;
		if (target < c->val)
			c = c->lchild;
		else
			c = c->rchild;
	}
	c = myNewNode();
	c->val = target;
	while (root != NULL)
	{
		if (target < p->val)
			c = c->lchild;
		else
			c = c->rchild;
	}
	
	return;
}

void print(tnode *r)
{
	if (r == NULL)
		return;
	print(r->lchild);
	cout << r->val;
	print(r->rchild);

	return;
}


int main()
{
	ifstream inFile;
	inFile.open("C://Users//Thuy//Desktop//372 Data Structures//Trees//Trees//test.txt");
	int num;

	while (inFile)
	{
		inFile >> num;
		insert(root, num);
	}

	print(root);

	inFile.close();

    return 0;
}