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())
s=raw_input()

ans=[]
prime=[2,3,5,7]
for x in s:
	y=int(x)
	
	if(y in prime):
		ans.append(y)
	else:
		i=y
		if(i==4):
			ans.append(2)
			ans.append(2)
			ans.append(3)
		elif(i==6):
			ans.append(5)
			ans.append(3)
		elif(i==8):
			ans.append(7)
			ans.append(2)
			ans.append(2)
			ans.append(2)
		elif(i==9):
			ans.append(3)
			ans.append(3)
			ans.append(2)
			ans.append(7)

ans.sort()
n=len(ans)
p=""
for i in range(n-1,-1,-1):
	p+=str(ans[i])	
print p
	
