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())
x=input().strip('0')
x=int(x)
y=[]
'''
0, 1 -> empty

2 -> 2

3 -> 3

4 -> 322

5 -> 5

6 -> 53

7 -> 7

8 -> 7222

9 -> 7332'''
d=dict(zip(range(2,10),[2, 3, 322, 5, 53, 7, 7222, 7332]))
#print(d)
a=[]
for i in range(n):
    c=x%10
  #  print(c)
    x//=10
    if(c!=1 and c!=0):
        y.append(str(d[c]))
        a.extend(str(d[c]))
    #else:
       # pass
a.sort(reverse=True)
print(''.join(a))
