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=int(input())
s1=str(input())
a=list(s1)
list1=[int(c) for c in a]
list2=[]
for i in range(n):
    if list1[i]==2:
        list2.append(2)
    elif list1[i]==3:
        list2.append(3)
    elif list1[i]==4:
        list2.append(3)
        list2.append(2)
        list2.append(2)
    elif list1[i]==5:
        list2.append(5)
    elif list1[i]==6:
        list2.append(3)
        list2.append(5)
    elif list1[i]==7:
        list2.append(7)
    elif list1[i]==8:
        list2.append(7)
        list2.append(2)
        list2.append(2)
        list2.append(2)
    elif list1[i]==9:
        list2.append(7)
        list2.append(3)
        list2.append(3)
        list2.append(2)
list2.sort()
list2.reverse()
#print(list2)
list3=[str(x) for x in list2]
print(''.join(list3))