class Node:
    def _init_ (self,val):
        self.val = val
        self.left = self.rright = Nonee
         
    def insert(root,key):
        
        if not root:
            return Node(key)
        if key<root val:
            root.left = insert(root.leaf,key)
        else:
            root.right = insert(root.right,key)
        return root
        
    def inorder(root):
        if root:
            inorder(root.left)
            print(root.val)
            inorder(root.right)
try:
    n = int(input())
    if n==0:
        print("Tree is Empty")
    else:
        root = Non
        for_inrange(n):
            root = insert(root,int(input()))
        inorder(root)
except:
    print("Invalid input")