Excellent Numbers

Time limit: 0.05s Memory limit: 64MB Input: Output:

Valerio was recently introduced to the concept of excellent numbers:
a positive integer is considered excellent if its decimal representation only contains the digits 11 and 55, and it is divisible by 33.

For example, 1515 and 111111 are excellent numbers (15=53+015 = 5\cdot 3 + 0 and 111=373+0111=37\cdot 3 + 0), while 151151 is not (151=503+1151 = 50 \cdot 3 + 1).

Valerio is wondering if there exists at least one excellent number with exactly NN digits.
Help him by finding one, or by determining that there are no excellent numbers with that number of digits!

Input data

The first (and only) line contains the integer NN.

Output data

You need to write a single line with an integer: an excellent number with NN digits, if there exists any. If there are multiple solutions, you may print any. Otherwise, if there is no such number, output 1-1.

Constraints and clarifications

  • 1N1 000 0001 \leq N \leq 1 \ 000 \ 000;
  • For tests worth 3333 points, N7N \le 7.
  • For tests worth 3333 more points, NN is even.







In the first sample case the number 1515 is a valid excellent number. 5151 is a correct answer, too.

Log in or sign up to be able to send submissions!