515_C. Drazil and Factorial
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>
```python
#in the name of god
#Mr_Rubik
#CodeForces,Problemset
sepData=[[],[],[2],[3],[2,2,3],[5],[5,3],[7],[7,2,2,2],[7,2,3,3]]
digit=input()
number=input()
ans=[]
for i in number:
    if i!='1' and i!='\r':
        for j in sepData[int(i)]:
            ans.append(j)
ans.sort(reverse=True)
for i in ans:
    print(i,end="")
```