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=input()
s=map(int,raw_input())
p=[0,0,0,0]
f=[[0,0,0,0],[0,0,0,0],[1,0,0,0],[0,1,0,0],[2,1,0,0],[0,0,1,0],[0,1,1,0],[0,0,0,1],[3,0,0,1],[1,2,0,1]]
r=[0,0,0,0]
for i in s:
    for j in xrange(4):
        r[j]+=f[i][j]
s=[2]*r[0]+[3]*r[1]+[5]*r[2]+[7]*r[3]
s.sort()
s=s[::-1]
s=map(str,s)
print ''.join(s)