题目描述
Problem statement
Of the string set $ S $ that meets the following conditions, configure $ 1 $ with the largest number of elements.
- The length of the string contained in $ S $ is $ 1 $ or more and $ N $ or less.
- The lengths of the strings contained in $ S $ are different.
- The string contained in $ S $ consists only of the characters
0and1. - For any $ 2 $ string contained in $ S $, one is not a substring of the other.
However, the substring of the string $ x $ is the string obtained by removing more than $ 0 $ characters from the beginning and end of $ x $.
Constraint
- $1 \ leq N \ leq 300$
- $ N $ is an integer
input
Input is given from standard input in the following format.
$ N $
output
Output $ 1 $ of the string set $ S $ that satisfies the condition with the maximum number of elements. There may be multiple such $ S $, but any output will be correct.
Specifically, output in the following format.
Output $ K $, the number of elements of $ S $, on the $ 1 $ line.
Output all $ S $ elements from the $ 2 $ line to the $ K + 1 $ line. Print $ 1 $ of $ S $ elements on each line.
$ K $
$ S_1 $
$ S_2 $
$\$
$ S_K $
Input example 1
2
Output example 1
2
0
11
The string set $\\ {0, 11 \\}$ is the set with the largest number of elements that meets the conditions.
Input example 2
1
Output example 2
1
0
Example
Input
2
Output
2
0
11
输入格式
见题面
输出格式
见题面