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>
from sys import stdin
di = {}
a = '0123456789'
for i in xrange(10):
 di[a[i]]=i
fa = [1]
for i in xrange(1,15):
 fa.append(i*fa[i-1])
n = stdin.readline()
n = stdin.readline().strip()
ans = 1
for i in n:
 ans = ans*fa[di[i]]
res = ''
while ans%5040==0:
 res = res+'7';ans = ans/5040
while ans%120==0:
 res = res+'5' ; ans = ans/120
while ans%6==0:
 res = res+'3';ans = ans/6
while ans%2==0:
 res = res+'2';ans = ans/2
print res