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()
L=list(raw_input())
N=[];M=[]
for i in L:
    if i=='2':
        N.append(2)
    if i=='3':
        N.append(3)
    if i=='4':
        N.extend([2,2,3])
    if i=='5':
        N.append(5)
    if i=='6':
        N.extend([5,3])
    if i=='7':
        N.append(7)
    if i=='8':
        N.extend([7,2,2,2])
    if i=='9':
        N.extend([7,2,3,3])
#print N
N.sort()
N.reverse()
for i in N:
    M.append(str(i))
print ''.join(M)
