程序员面试100题之十二，从上往下遍历二元树

// 100_12.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <queue>

struct Node
{
	Node * left;
	Node * right;
	int value;
};

void visit(Node * root)
{
	if(!root)
		return;

	std::queue<Node*> q;
	q.push(root);

	while(!q.empty())
	{
		Node * temp = q.front();
		q.pop();
		printf("%d ",temp->value);

		if(temp->left)
			q.push(temp->left);
		if(temp->right)
			q.push(temp->right);
	}
}


int _tmain(int argc, _TCHAR* argv[])
{
	Node * n1 = new Node();
	Node * n2 = new Node();
	Node * n3 = new Node();
	
	n1->left = n2;
	n1->right = n3;
	n1->value = 1;

	n2->left = NULL;
	n2->right = NULL;
	n2->value = 2;

	n3->left = NULL;
	n3->right = NULL;
	n3->value = 3;

	visit(n1);

	return 0;
}