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
import math
import bisect

def solve(s):
    #print('s: %s' % s)
    n = len(s)
    A = []
    for i in range(n):
        val = ord(s[i]) - ord('0')
        #print('val: %d' % (val))
        if val == 2:
            A.extend([2])
        elif val == 3:
            A.extend([3])
        elif val == 4:
            A.extend([3, 2, 2])
        elif val == 5:
            A.extend([5])
        elif val == 6:
            A.extend([5, 3])
        elif val == 7:
            A.extend([7])
        elif val == 8:
            A.extend([7, 2, 2, 2])
        elif val == 9:
            A.extend([7, 3, 3, 2])
    A.sort(reverse=True)
    return ''.join(list(str(a) for a in A))

def main():
    n = int(input())
    s = input()
    ans = solve(s)
    print(ans)
    
if __name__ == "__main__":
    main()
