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>

# raw_input

d = {
	2:[2],
	3:[3],
	4:[2,2,3],
	5:[5],
	6:[3,5],
	7:[7],
	8:[2,2,2,7],
	9:[3,3,2,7]
}

def main():
	raw_input()
	n = [ int(c) for c in raw_input().strip() if c not in "01" ]
	x = []
	for c in n:
		x.extend(d[c])
	x = sorted(x)[::-1]
	print "".join(str(c) for c in x)


main()