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

struct BTree{
	struct BTree *left;
	struct BTree *right;
	int val;
}Tree;

//这里假设为完全二叉树故判断条件有一个index>v.size()
void creTree(struct BTree* head,vector<int>v,int index){
	if(v.size()==0||head==NULL||index>v.size()||index<0)return;
	int last=v.size()-1;
	if(2*index+1<=last){
		head->left=new struct BTree();
		head->left->val=v[2*index+1];
	}else{
		head->left=NULL;
	}
	if(2*index+2<=last){
		head->right=new struct BTree();
		head->right->val=v[2*index+2];
	}else{
		head->right=NULL;
	}
	creTree(head->left,v,2*index+1);
	creTree(head->right,v,2*index+2);
}
struct BTree * create(vector<int>v){
	if(v.size()==0){
		return NULL;
	}
	struct BTree* head=new struct BTree();
	head->val=v[0];
	creTree(head,v,0);
	return head;
}

int main(){
	int n;
	scanf("%d",&n);
	vector<int>v(n);
	for(int i=0;i<n;++i){
		scanf("%d",&v[i]);
	}
	struct BTree* head=new struct BTree();
	head=create(v);
  
  //以下为层次遍历二叉树，查看是否正确
	queue<struct BTree*>q;
	if(head!=NULL){
		q.push(head);
	}
	while(!q.empty()){
		cout<<q.front()->val<<" ";
		
		if(q.front()->left){
			q.push(q.front()->left);
		}
		if(q.front()->right){
			q.push(q.front()->right);
		}
		q.pop();
	}
	return 0;
}