/*

struct TreeNode {

	int val;

	struct TreeNode *left;

	struct TreeNode *right;

	TreeNode(int x) :

			val(x), left(NULL), right(NULL) {

	}

};*/

class Solution {

public:

    vector<int> PrintFromTopToBottom(TreeNode* root) {

        queue<TreeNode*>q;

        vector<int>vt;

        if(root == NULL)

            return vt;

        q.push(root);

        vt.push_back(root->val);

        while(!q.empty()){

            TreeNode* tmp = q.front();

            q.pop();

            if(tmp->left != NULL){

                vt.push_back(tmp->left->val);

                q.push(tmp->left);

            }

            if(tmp->right != NULL){

                vt.push_back(tmp->right->val);

                q.push(tmp->right);

            }

        }

        return vt;

    }

};