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 sys
input =sys.stdin.readline
x = int(input())
y  =int(input())
y = str(y)
li = [0]*10
li[2] = [2]
li[3] = [3]
li[4] = [3, 2, 2]
li[5] = [5]
li[6 ] = [5, 3]
li[7] = [7]
li[8] = [7, 2, 2, 2]
li[9] =  [7, 3, 3, 2]
li1 = []
for i in y:
	if i=='0'or i== '1':
		pass
	else:
		i = int(i)
		for j in li[i]:
			li1.append(j)
li1.sort(reverse= True)
str1= ''
for i in li1:
	str1 += str(i)
print(str1)
