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>
a=input()
b=list(input())
c=[]
for i in range(len(b)):
    if(b[i]=='2'):
        c.append('2')
    if(b[i]=='3'):
        c.append('3')
    if(b[i]=='5'):
        c.append('5')
    if(b[i]=='7'):
        c.append('7')
    if(b[i]=='4'):
        c.append('2')
        c.append('2')
        c.append('3')
    if(b[i]=='6'):
        c.append('3')
        c.append('5')
    if(b[i]=='8'): 
         c.append('2')
         c.append('2')
         c.append('2')
         c.append('7')
    if(b[i]=='9'):
        c.append('3')
        c.append('3')
        c.append('2')
        c.append('7')
c.sort()
d=''
for i in range(len(c)-1,-1,-1):
    d+=c[i]
print(d)