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>
def findclosestprime(n):
    if n==4:
        return 3
    elif n==6:
        return 5
    else:
        return 7
t=int(input())
k=input()
k=k.strip("0")
s=1
finalres=[]
for i in k:
    j=int(i)
    if j==0 or j==1:
        continue
    if j==2 or j==3 or j==5 or j==7:
        finalres.append(j)
    else:
        l=findclosestprime(j)
        finalres.append(l)
        if j==9:
            j=72
        while(j%6==0):
            finalres.append(3)
            j=j//6
        while(j>1):
            finalres.append(2)
            j=j//2
print(*(sorted(finalres,reverse=True)),sep="")