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>
def getL(n):
  if n == 2 or n == 3 or n == 5 or n == 7:
    return [n]
  elif n == 4:
    return [3,2,2]
  elif n == 6:
    return [5,3]
  elif n == 8:
    return [7,2,2,2]
  elif n == 9:
    return [7,3,3,2]
  else:
    return []

input()
s = input().strip()
ret = []
for i in s:
  ret += getL(int(i))
ret.sort()
print(''.join([str(i) for i in ret[::-1]]))
