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>
list4=[3,2,2]
list6=[5,3]
list8=[7,2,2,2]
list9=[7,3,3,2]
numi=[]
t=int(raw_input())
num=int(raw_input())
ans=1
while num>0:
    x=num%10
    if x==2:
        numi.append(2)
    elif x==3:
        numi.append(3)
    elif x==4:
        numi.extend(list4)
    elif x==5:
        numi.append(5)
    elif x==6:
        numi.extend(list6)
    elif x==7:
        numi.append(7)
    elif x==8:
        numi.extend(list8)
    elif x==9:
        numi.extend(list9)
    num=num/10
numi.sort()
numi.reverse()
print "".join(map(str,numi))