Drazil is playing a math game with Varda.

Let's define for positive integer $*x*$ as a product of factorials of its digits. For example, .

First, they choose a decimal number $*a*$ consisting of $*n*$ digits that contains at least one digit larger than $1$. This number may possibly start with leading zeroes. Then they should find maximum positive number $*x*$ satisfying following two conditions:

1. $*x*$ doesn't contain neither digit $0$ nor digit $1$.

2. = .

Help friends find such number.

Input

The first line contains an integer $*n*$ ($1 ≤ *n* ≤ 15$) — the number of digits in $*a*$.

The second line contains $*n*$ digits of $*a*$. There is at least one digit in $*a*$ that is larger than $1$. Number $*a*$ may possibly contain leading zeroes.

Output

Output a maximum possible integer satisfying the conditions above. There should be no zeroes and ones in this number decimal representation.

Note

In the first case,