Drazil is playing a math game with Varda.

Let's define <image> for positive integer x as a product of factorials of its digits. For example, <image>.

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. <image> = <image>.

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.

Examples

Input

4
1234


Output

33222


Input

3
555


Output

555

Note

In the first case, <image>
# -*- coding: utf-8 -*-

n = int(raw_input())
s = map( int, raw_input() )

d = {}

d[2] = [2]
d[3] = [3]
d[4] = [2,2,3]
d[5] = [5]
d[6] = [5, 3]
d[7] = [7]
d[8] = [2,2,2,7]
d[9] = [7, 3,3, 2]


out = []
for i in s:
  if i > 1:
    out.extend( d[i] )

out.sort(reverse=True)

print ''.join( map(str, out) )
