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>
n = int(input())
a = input()
dic = {2:0, 3:0, 5:0, 7:0}

for ch in a:
  if ch == '2':
    dic[2] += 1
  elif ch == '3':
    dic[2] += 1
    dic[3] += 1
  elif ch == '4':
    dic[2] += 3
    dic[3] += 1
  elif ch == '5':
    dic[2] += 3
    dic[3] += 1
    dic[5] += 1
  elif ch == '6':
    dic[2] += 4
    dic[3] += 2
    dic[5] += 1
  elif ch == '7':
    dic[2] += 4
    dic[3] += 2
    dic[5] += 1
    dic[7] += 1
  elif ch == '8':
    dic[2] += 7
    dic[3] += 2
    dic[5] += 1
    dic[7] += 1
  elif ch == '9':
    dic[2] += 7
    dic[3] += 4
    dic[5] += 1
    dic[7] += 1

x = ''

x += '7' * dic[7]
dic[2] -= 4 * dic[7]
dic[3] -= 2 * dic[7]
dic[5] -= 1 * dic[7]
x += '5' * dic[5]
dic[2] -= 3 * dic[5]
dic[3] -= 1 * dic[5]
x += '3' * dic[3]
dic[2] -= 1 * dic[3]
x += '2' * dic[2]

print(x)