Time Limit: 1000MS

Memory Limit: 10000K

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## Description

We can number binary trees using the following scheme: The empty tree is numbered 0. The single-node tree is numbered 1. All binary trees having m nodes have numbers less than all those having m+1 nodes. Any binary tree having m nodes with left and right subtrees L and R is numbered n such that all trees having m nodes numbered > n have either Left subtrees numbered higher than L, or A left subtree = L and a right subtree numbered higher than R. The first 10 binary trees and tree number 20 in this sequence are shown below: Your job for this problem is to output a binary tree when given its order number.

## Input

Input consists of multiple problem instances. Each instance consists of a single integer n, where 1 <= n <= 500,000,000. A value of n = 0 terminates input. (Note that this means you will never have to output the empty tree.)

## Output

For each problem instance, you should output one line containing the tree corresponding to the order number for that instance. To print out the tree, use the following scheme: A tree with no children should be output as X. A tree with left and right subtrees L and R should be output as (L')X(R'), where L' and R' are the representations of L and R. If L is empty, just output X(R'). If R is empty, just output (L')X.

## Sample Input

1
20
31117532
0

## Sample Output

X
((X)X(X))X
(X(X(((X(X))X(X))X(X))))X(((X((X)X((X)X)))X)X)

## Source

East Central North America 2001