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()
a=raw_input()
fac=list()
a=map(int,str(a))
ans=""
non_zero=False
#0check
'''
for i in range(len(a)):
    if a[i]!=0 and a[i]!=1:
        non_zero=True

if non_zero==False:
    a=map(str,a)
    #print a
    for i in range(len(a)):
        ans+=a[i]
    #print "sd",ans
    print int(ans)
    exit(0)
'''
for i in range(len(a)):
    if a[i]==2:
        fac.append(2)
    if a[i]==3:
        fac.append(3)
    if a[i]==4:
        fac.append(2)
        fac.append(3)
        fac.append(2)
    if a[i]==5:
        fac.append(5)
    if a[i]==6:
        fac.append(5)
        fac.append(3)
    if a[i]==7:
        fac.append(7)
    if a[i]==8:
        fac.append(7)
        fac.append(2)
        fac.append(2)
        fac.append(2)
    if a[i]==9:
        fac.append(7)
        fac.append(3)
        fac.append(3)
        fac.append(2)
     

fac=sorted(fac, reverse=True)
#print fac
fac=map(str,fac)
for i in range(len(fac)):
    ans+=fac[i]
print int(ans)
