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>



if __name__=="__main__":
    n=int(input())
    s=str(input())

    res=""

    for i in range(n):
        if s[i]=='0' or s[i]=='1': continue

        if s[i]=='4': res+="322"
        elif s[i]=='6': res+="53"
        elif s[i]=='8': res+="7222"
        elif s[i]=='9': res+="7332"
        else: res+=s[i]
    res=''.join(sorted(res,reverse=True))
    
    print(res)
