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())
str1=input()
mp={}
lst = ['2','3','5','7']
for i in str1:
    if i in lst:
        if i in mp.keys():
            mp[i]+=1
        else:
            mp[i]=1
    elif i=='4':
        if '3' in mp.keys():
            mp['3']+=1
        else:
            mp['3']=1
        if '2' in mp.keys():
            mp['2']+=2
        else:
            mp['2']=2
    elif i=='6':
        if '3' in mp.keys():
            mp['3']+=1
        else:
            mp['3']=1
        if '5' in mp.keys():
            mp['5']+=1
        else:
            mp['5']=1
    elif i=='8':
        if '7' in mp.keys():
            mp['7']+=1
        else:
            mp['7']=1
        if '2' in mp.keys():
            mp['2']+=3
        else:
            mp['2']=3
    elif i=='9':
        if '7' in mp.keys():
            mp['7']+=1
        else:
            mp['7']=1
        if '2' in mp.keys():
            mp['2']+=1
        else:
            mp['2']=1
        if '3' in mp.keys():
            mp['3']+=2
        else:
            mp['3']=2
    #print(mp)
for key in reversed(sorted(mp.keys())):
    print(key*mp[key],end="")
        
        
        
    