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>
#: Author - Soumya Saurav
import sys,io,os,time
from collections import defaultdict
from collections import OrderedDict
from collections import deque
from itertools import combinations
from itertools import permutations
import bisect,math,heapq
alphabet = "abcdefghijklmnopqrstuvwxyz"

#input = sys.stdin.readline

########################################
mydic = {2 : 2, 3:3, 4:322, 5:5, 6:53, 7:7, 8:7222, 9 : 7332}
n = int(input())
s = input()
count = defaultdict(int)

for i in s:
	#print(i,count)
	count[int(i)]+=1

count = sorted(count.items(), key = lambda x : x[1], reverse = True)
#print(count)
ans = ""
for k,v in count:
	if k == 1 or k == 0:
		continue
	ans+=str(mydic[k])*v
ans = sorted(list(ans), key = lambda x: int(x),reverse = True)
print("".join(ans))






