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()
n=int(n)
s=input()
a=[]
for i in range(10):
    a.append(0)
for i in range(n):
    if s[i]=='2':
        a[2]+=1
    elif s[i]=='3':
        a[3]+=1
    elif s[i]=='4':
        a[3]+=1
        a[2]+=2
    elif s[i]=='5':
        a[5]+=1
    elif s[i]=='6':
        a[5]+=1
        a[3]+=1
    elif s[i]=='7':
        a[7]+=1
    elif s[i]=='8':
        a[7]+=1
        a[2]+=3
    elif s[i]=='9':
        a[7]+=1
        a[2]+=1
        a[3]+=2
       
for i in range(9,-1,-1):
    if a[i]>0:
        while a[i]>0:
            print(i,end='')
            a[i]-=1
