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>
#!usr/bin/python
n=int(input())
s=raw_input()
s2="2"
s3="3"
s4="322"
s5="5"
s6="53"
s7="7"
s8="7222"
s9="7332"
sR=""
for i in range(n):
    if(s[i]=="2"):
        sR=sR+s2
    if(s[i]=="3"):
        sR=sR+s3
    if(s[i]=="4"):
        sR=sR+s4
    if(s[i]=="5"):
        sR=sR+s5
    if(s[i]=="6"):
        sR=sR+s6
    if(s[i]=="7"):
        sR=sR+s7
    if(s[i]=="8"):
        sR=sR+s8
    if(s[i]=="9"):
        sR=sR+s9
sR=sorted(sR)
sR=''.join(sR)
print sR[::-1]




