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>
'''input
3
555
'''
p=int(input())
n=int(input())
l=[0]*10
while n>0:
	temp=n%10
	for i in range(2,temp+1):
		l[i]+=1
	n//=10
l[2]=l[2]+2*l[4]+l[6]+3*l[8]
l[3]=l[3]+l[6]+2*l[9]
if l[4]!=0:
	l[4]=-1
if l[6]!=0:
	l[6]=-1
if l[8]!=0:
	l[8]=-1
if l[9]!=0:
	l[9]=-1
ans=""
for i in range(len(l)-1,-1,-1):
	if l[i]>0:
		ans+=str(i)*l[i]
		for j in range(i-1,1,-1):
			if l[j]>0:
				#ans+=str(j)*l[i]
				l[j]-=l[i]
			elif j==9:
				l[3]-=2*l[i]
			elif j==8:
				l[2]-=3*l[i]
			elif j==6:
				l[3]-=l[i]
				l[2]-=l[i]
			elif j==4:
				l[2]-=2*l[i]
		l[i]=0
print(ans)