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=int(input())
a=list(map(int,input()))
b=list()
for i in a:
	if i==2:
		b.append(2)
	elif i==3:
		b.append(3)
	elif i==4:
		b.extend([3,2,2])
	elif i==5:
		b.append(5)
	elif i==6:
		b.extend([5,3])
	elif i==7:
		b.append(7)
	elif i==8:
		b.extend([7,2,2,2])
	elif i==9:
		b.extend([7,3,3,2])
b.sort()
b.reverse()
c=list(map(str,b))
print("".join(c))