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>
# from itertools import combinations
# from bisect import bisect_right
# from functools import *
# from collections import ByteString

# I = lambda: list(map(int, input().split()))

_ = input()
s = input()
a = []
for dig in map(int, s):
	if dig == 1 or dig == 0:
		continue
	if dig == 4:
		a += [2, 2, 3]
	elif dig == 6:
		a += [3, 5]
	elif dig == 8:
		a += [7, 2, 2, 2]
	elif dig == 9:
		a += [2, 3, 3, 7]
	else:
		a += [dig]
print(''.join(map(str, sorted(a, reverse=True))))