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=list(input())
x=[]
for i in range(n):
    a[i]=int(a[i])
for i in range(n):
    if a[i]<=3:
        x.append(a[i])
    else:
        if a[i]%2!=0 and a[i]<9:
            x.append(a[i])
        else:
            if a[i]==4:
                x.append(2)
                x.append(2)
                x.append(3)
            if a[i]==6:
                x.append(3)
                x.append(5)
            if a[i]==8:
                x.append(2)
                x.append(2)
                x.append(2)
                x.append(7)
            if a[i]==9:
                x.append(3)
                x.append(3)
                x.append(2)
                x.append(7)
            
x.sort()
ans=0
if 1 in x:
    while 1 in x:
        x.remove(1)
if 0 in x:
    while 0 in x:
        x.remove(0)
for i in range(len(x)):
    ans+=x[i]*(10**(i))
print(ans)
                
        
