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>
import sys
n = int (sys.stdin.readline())
s = sys.stdin.readline().strip()
ans = ""
for c in s:
  if c == '2' or c == '3' or c =='5' or c == '7':
    ans = ans + c
  if c == '4':
    ans = ans + '322'
  if c == '6':
    ans = ans + '53'
  if c == '8':
    ans = ans + '7222'
  if c == '9':
    ans = ans + '7332'

ans = ''.join(sorted(ans))
print (ans[::-1])