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(raw_input())
s = raw_input()
lis = []
for i in xrange(n):
	if s[i]=='1' or s[i]=='0':
		continue
	elif s[i]=='2':
		lis.append(2)
	elif s[i]=='3':
		lis.append(3)
	elif s[i]=='4':
		lis.append(2)
		lis.append(2)
		lis.append(3)
	elif s[i]=='5':
		lis.append(5)
	elif s[i]=='6':
		lis.append(3)
		lis.append(5)
	elif s[i]=='7':
		lis.append(7)
	elif s[i]=='8':
		lis.append(2)
		lis.append(2)
		lis.append(2)
		lis.append(7)
	elif s[i]=='9':
		lis.append(7)
		lis.append(3)
		lis.append(3)
		lis.append(2)
lis = sorted(lis, reverse= True)
print ''.join(str(k) for k in lis)
