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Description

A Gray code is a list of all 2n bit strings of length n, where any two successive strings differ in exactly one bit (i.e., their Hamming distance is one).

Your task is to create a Gray code for a given length n.

Input Format

The only input line has an integer n.

Output Format

Print 2ⁿ lines that describe the Gray code. You can print any valid solution.

2

00
01
11
10

Hint

1≤n≤16

Source

CSES