#include <iostream>

using namespace std;

class Node

{

public:

int data;

Node* left;

Node* right;

Node(int d, Node* l, Node* r) :data(d), left(l), right(r) {};

Node() : data(0), left(nullptr), right(nullptr) {};

};

class Tree

{

public:

Node * root;

int num;

Tree() :root(nullptr), num(0) {};

Node* search(Node* node, int data)

{

if (node == nullptr) return nullptr;

if (data == node->data) return node;

else if (data < node->data) search(node->left, data);

else search(node->right, data);

}

void insertNode(int data)

{

Node* cur = root;

Node* parent = nullptr;

if (root == nullptr)

root = new Node(data, nullptr, nullptr);

else

{

while (1)

{

if (data > cur->data)

{

if (cur->right == nullptr)

{

cur->right = new Node(data, nullptr, nullptr);

break;

}

cur = cur->right;

}

else

{

if (cur->left == nullptr)

{

cur->left = new Node(data, nullptr, nullptr);

break;

}

cur = cur->left;

}

}

}

num++;

}

Node* getRoot()

{

return root;

}

void preorder(Node* node)

{

if (node == nullptr) return;

cout << node->data << ' ';

preorder(node->left);

preorder(node->right);

}

};

int main()

{

ios::sync_with_stdio(false);

cin.tie(NULL);

Tree T;

int n = 0, data = 0;

cin >> n;

for (int i = 0; i<n; i++)

{

cin >> data;

T.insertNode(data);

}

T.preorder(T.getRoot());

return 0;

}