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# Problem JOrdinals

The Von Neumann ordinals are a number system. Ordinal numbers can be represented as sets of all numbers less than that number:

\begin{aligned} 0 & = \varnothing & =& \ \{ \} \\ 1 & = \{ 0\} & =& \ \{ \{ \} \} \\ 2 & = \{ 0,1\} & =& \ \{ \{ \} ,\{ \{ \} \} \} \\ 3 & = \{ 0,1,2\} & =& \ \{ \{ \} ,\{ \{ \} \} ,\{ \{ \} ,\{ \{ \} \} \} \} \\ & \vdots \end{aligned}

## Input

Input consists of a single integer $0 \le n \le 8$.

## Output

The output is the representation of that number as a set as specified above.

Sample Input 1 Sample Output 1
0

{}

Sample Input 2 Sample Output 2
1

{{}}

Sample Input 3 Sample Output 3
2

{{},{{}}}


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