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>
a=int(input())

b=input()

l=[]

for i in range(len(b)):
    if b[i]!="0" or b[i]!="1":
        if b[i]=="2":
            p=int(b[i])
            l.append(p)
        elif b[i]=="3":
            p=int(b[i])
            l.append(p)
        elif b[i]=="5":
            p=int(b[i])
            l.append(p)
        elif b[i]=="7":
            p=int(b[i])
            l.append(p)
        elif b[i]=="4":
            l.append(3)
            l.append(2)
            l.append(2)
        elif b[i]=="6":
            l.append(3)
            l.append(5)
        elif b[i]=="8":
            l.append(2)
            l.append(2)
            l.append(2)
            l.append(7)
        elif b[i]=="9":
            l.append(7)
            l.append(3)
            l.append(3)
            l.append(2)

s=""


for i in range(len(l)):
    n=max(l)
    s=s+str(n)
    l.remove(n)

print(s)