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()
s=str(raw_input())
ans=[]
for i in s:
    f=[]
    i=int(i)
    if i==2:
        f=[2]
    if i==3:
        f=[3]
    if i==4:
        f=[2,2,3]
    if i==5:
        f=[5]
    if i==6:
        f=[5,3]
    if i==7:
        f=[7]
    if i==8:
        f=[7,2,2,2]
    if i==9:
        f=[7,3,3,2]
    ans=ans+f

ans.sort(reverse=True)
#print ans
q=""
for i in range(0,len(ans)):
    q=q+str(ans[i])
print q