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>
import heapq
n=int(input())
s=input()
l=[]
for i in s:
    l.append(int(i))
ans=[]
for j in l:
    if j==2 or j==3 or j==5 or j==7:
        ans.append(j)
    elif j==4:
        ans+=[3,2,2]
    elif j==6:
        ans+=[5,3]
    elif j==8:
        ans+=[7,2,2,2]
    elif j==9:
        ans+=[7,3,3,2]
#print(ans)
heapq._heapify_max(ans)
m=''
while ans:
    x=heapq._heappop_max(ans)
    m+=str(x)
print(int(m))