P2192 HXY Plays with Cards

HXY has some cards, each labeled with the digit $0$ or $5$. She can choose some of these cards and arrange them in a row to form the largest possible number that is divisible by $90$. This number must be a valid non-negative integer, meaning it cannot have a leading $0$; that is, $0$ cannot be the first digit of the sequence. Exceptionally, the integer $0$ is allowed. If no such number can be formed, output $-1$.

The first line contains the number of cards $n$. The second line contains the $n$ digits (each is either $5$ or $0$).

Output a single line: if it is possible, print the number; otherwise, print $-1$.

Constraints: For $30\%$ of the testdata, $n \le 10$. For $20\%$ of the testdata, all given digits are $5$. For $100\%$ of the testdata, $n \le 1000$. Translated by ChatGPT 5