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())
a=[int(x) for x in list(input())]
fac={2:0,3:0,5:0,7:0}
ans=[]
for i in range(2,10):
    t=a.count(i)
    if i==9:
        fac[2]+=7*t
        fac[3]+=4*t
        fac[5]+=t
        fac[7]+=t
    if i==8:
        fac[2]+=7*t
        fac[3]+=2*t
        fac[5]+=t
        fac[7]+=t
    if i==7:
        fac[2]+=4*t
        fac[3]+=2*t
        fac[5]+=t
        fac[7]+=t
    if i==6:
        fac[2]+=4*t
        fac[3]+=2*t
        fac[5]+=t
    if i==5:
        fac[2]+=3*t
        fac[3]+=t
        fac[5]+=t
    if i==4:
        fac[2]+=3*t
        fac[3]+=t
    if i==3:
        fac[2]+=t
        fac[3]+=t
    if i==2:
        fac[2]+=t
for i in [7,5,3,2]:
    t=fac[i]
    ans=ans+[i]*t
    if i==7:
        fac[2]-=4*t
        fac[3]-=2*t
        fac[5]-=t
        fac[7]-=t
    if i==5:
        fac[2]-=3*t
        fac[3]-=t
        fac[5]-=t
    if i==3:
        fac[2]-=t
        fac[3]-=t
ans.sort(reverse=True)
print(''.join([str(x) for x in ans]))
