# 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 $1$ and $5$, and it is divisible by $3$.

For example, $15$ and $111$ are excellent numbers ($15 = 5\cdot 3 + 0$ and $111=37\cdot 3 + 0$), while $151$ is not ($151 = 50 \cdot 3 + 1$).

Valerio is wondering if there exists at least one excellent number with exactly $N$ 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 $N$.

## Output data

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

## Constraints and clarifications

• $1 \leq N \leq 1 \ 000 \ 000$;
• For tests worth $33$ points, $N \le 7$.
• For tests worth $33$ more points, $N$ is even.

## Example

stdin

2


stdout

15


### Explanation

In the first sample case the number $15$ is a valid excellent number. $51$ is a correct answer, too.