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(input())

a=str(a)
pf={'2':['2'],'3':['3'],'4':['2','2'],'5':['5'],'6':['3','2'],'7':['7'],'8':['2','2','2'],'9':['3','3']}

def fact(n):
    nn=int(n)
    res=[]
    while nn>=2:
        res+=pf[str(nn)]
        nn-=1
    return res

fx=[]
for d in a: fx+=fact(d)

freq={}
for n in fx:
    if n not in freq: freq[n]=0
    freq[n]+=1

pfact={'7':{'7':1,'5':1,'3':2,'2':4},'5':{'5':1,'3':1,'2':3},'3':{'3':1,'2':1},'2':{'2':1}}



ans=''
for p in ['7','5','3','2']:
    if p not in freq: continue
    for _ in range(freq[p]):
        ans+=p
        for pp in pfact[p]:
            freq[pp]-=pfact[p][pp]

print(ans)

       

