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 main():
    raw_input()
    S = raw_input()
    
    H = {
        0:[],
        1:[],
        2:[2],
        3:[3],
        4:[2,2,3],
        5:[5],
        6:[5,3],
        7:[7],
        8:[2,2,2,7],
        9:[7,3,3,2]
    }
    res = {}
    for i in S:
        k = int(i)
        for j in H[k]:
            if j not in res:
                res[j] = 0
            res[j] += 1
    
    final = []
    for i in range(9,0,-1):
        if i in res:
            for Q in range(res[i]):
                final.append(str(i))
    
    print "".join(final)
    
main()