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Problem A
Base-2 Palindromes

A positive integer N is a base-b palindrome if the base-b representation of N (with no leading zeros) is a palindrome, i.e. reads the same way in either direction. For instance, 7 (base 10) is a palindrome in any base greater than or equal to 8. It is also a palindrome in base 2 (111) and 6 (11), but not in 3 (21), 4 (13), 5 (12), or 7 (10). The first four base-2 palindromes (written in base 10) are 1, 3, 5, and 7.

Task

You are supposed to find the M-th base-2 palindrome and output its base-10 representation.

Input

The input is a single line with a single positive integer M50000 in base 10.

Output

The output for input M should be a single line with the base-10 representation of the M-th base-2 palindrome.

Sample Input 1 Sample Output 1
1
1
Sample Input 2 Sample Output 2
3
5
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