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>
input()
a = raw_input()
s = list(a)
r=[]
for i in range(len(s)):
    #print s[i]
    if s[i]=='9':
        r.append('7')
        r.append('3')
        r.append('3')
        r.append('2')
        #r[:]=list(r)
    if s[i]=='8':
        #e.append('7222')
        r.append('7')
        r.append('2')
        r.append('2')
        r.append('2')
    if s[i]=='7' or s[i]=='2' or s[i]=='5' or s[i]=='3':
        r.append(s[i])
    if s[i]=='6':
        r.append('5')
        r.append('3')
        #b[:]=list(b)
    if s[i]=='4':
        r.append('3')
        r.append('2')
        r.append('2')
        #[:]=list(c)
        #print list(c)

#a = r+e+b+c
#print r,e,b,c
(r).sort(reverse = True)
#print a
print ''.join(r)
        
