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())
a = raw_input().strip()
new_a = []
for e in a:
	e = int(e)
	if e > 1: new_a.append(e)
new_a = sorted(new_a, reverse=True)

counts = [0 for _ in range(10)]
for e in new_a:
	if e == 4:
		counts[3] += 1
		counts[2] += 2
	elif e == 6:
		counts[5] += 1
		counts[3] += 1
	elif e == 8:
		counts[7] += 1
		counts[2] += 3
	elif e == 9:
		counts[7] += 1
		counts[3] += 2
		counts[2] += 1
	else:
		counts[e] += 1

ans = ''
for i in range(9,1,-1):
	ans += str(i)*counts[i]

print ans
