module Main where

data Tree = Empty | Node Int Tree Tree

instance Show Tree where
    show Empty = ""
    show (Node x l r) =
        show l ++ show r ++ show x ++ " "

insert :: Tree -> Int -> Tree
insert Empty x = Node x Empty Empty
insert (Node k left right) x
    | x < k = Node k (insert left x) right
    | otherwise = Node k left (insert right x)

parseTree :: [Int] -> Tree
parseTree = foldl insert Empty

main :: IO ()
main = do
    _ <- getLine
    seq <- map read . words <$> getLine :: IO [Int]
    print $ parseTree seq

public static void postOrder(Node root) {
        if(root != null){
            postOrder(root.left);
            postOrder(root.right);
            System.out.print(root.data+" ");
        }
    }

function postOrder(root) {
	  let result = []
		let values = ""
    
    function dfsPostTraverse(currentNode){
        if(currentNode == null){
            return;
        }
        dfsPostTraverse(currentNode.left)
        dfsPostTraverse(currentNode.right)
        result.push(currentNode.data)
    }
    
    dfsPostTraverse(root)
    
    for(let i=0; i<result.length; i++){
        values += result[i] + " "
    }
    console.log(values)
}

def postOrder(root):
    result = []
    
    def traverse(node):
        if not node:
            return
        traverse(node.left)
        traverse(node.right)
        result.append(str(node.info))
        
    traverse(root)
    print(" ".join(result))