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>
# import sys
# sys.stdin = open("#input.txt", "r")

input()
st = input()

num = ['7','5','3','2']
res = [0]*4 #cnts 2,3,5,7

for c in st:
	if c == '9': res[1]+=2;res[0]+=1;res[3]+=1
	elif c == '8': res[0]+=3;res[3]+=1
	elif c == '7': res[3]+=1
	elif c == '6': res[1]+=1;res[2]+=1
	elif c == '5': res[2]+=1
	elif c == '4': res[0]+=2;res[1]+=1
	elif c == '3': res[1]+=1
	elif c == '2': res[0]+=1

for r,n in zip(reversed(res),num):
	print(n*r,end='')
