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())
s=input()
a=[int(x) for x in str(s)]
a.sort()
l=[]
#print(a)
c=0
for i in range(n):
    if(a[i]==1 or a[i]==0):
        c+=1
a=a[c:]
#print(a)
for i in range(len(a)):
    if(a[i] != 2 and a[i]&(a[i]-1)==0):
        res=a[i]
        c=0
        while(res%2==0):
            res//=2
            c+=1
        a[i]-=1
        l+=[2]*c
        #print(a[i],end=" ")
    elif(a[i]%6==0):
        c=0
        res=a[i]//6
        if(res&(res-1)==0):
            while(res%2==0):
                res//=2
                c+=1
            a[i]-=1
            l+=[3]+[2]*c
    elif(a[i]==9):
        a[i]-=2
        l+=[3]*2+[2]
a+=l

a.sort(reverse=True)
for i in range(len(a)):
    print(a[i],end="")
print()