Binary Tree Right Side View

Given a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom.

For example:
Given the following binary tree,

   1            <---
 /   2     3         <---
 \       5     4       <---

You should return [1, 3, 4].

#include<iostream>
#include<vector>
#include<queue>
using namespace std;

struct TreeNode {
	int val;
	TreeNode *left;
	TreeNode *right;
	TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};
vector<int> rightSideView(TreeNode *root) {
	vector<int>Result;
	if (root == NULL)
		return Result;
	queue<pair<TreeNode*, int>>Queuenode;
	TreeNode* TmpHead = root;
	Queuenode.push(make_pair(TmpHead, 0));
	pair<TreeNode*, int>deletenode(NULL, 0);
	while (!Queuenode.empty())
	{
		TmpHead = Queuenode.front().first;
		int curlevel = Queuenode.front().second;
		if (deletenode.second != curlevel)
			Result.push_back(deletenode.first->val);
		if (TmpHead->left)
			Queuenode.push(make_pair(TmpHead->left, curlevel + 1));
		if (TmpHead->right)
			Queuenode.push(make_pair(TmpHead->right, curlevel + 1));
		deletenode = Queuenode.front();
		Queuenode.pop();
	}
	Result.push_back(deletenode.first->val);
	return Result;
}