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=input()
a=raw_input()
lis=[]
for i in a:
    if i=='9':
        lis+=[7,3,3,2]
    if i=='8':
        lis+=[7,2,2,2]
    if i=='7':
        lis.append(7)
    if i=='6':
        lis+=[5,3]
    if i=='5':
        lis.append(5)
    if i=='4':
        lis+=[3,2,2]
    if i=='3':
        lis.append(3)
    if i=='2':
        lis.append(2)
lis.sort(reverse=True)
for i in range(len(lis)):
    lis[i]=str(lis[i])
print ''.join(lis)
 