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
n=int(input())
k=str(input())

#variables
f=[0,0,0,0]
j=''
def c(l,t):
	if t==2:
		f[0]+=1
	if t==3:
		f[0]+=1
		f[1]+=1
	if t==4:
		f[0]+=3
		f[1]+=1
	if t==5:
		f[0]+=3
		f[1]+=1
		f[2]+=1
	if t==6:
		f[0]+=4
		f[1]+=2
		f[2]+=1
	if t==7:
		f[0]+=4
		f[1]+=2
		f[2]+=1
		f[3]+=1
	if t==8:
		f[0]+=7
		f[1]+=2
		f[2]+=1
		f[3]+=1
	if t==9:
		f[0]+=7
		f[1]+=4
		f[2]+=1
		f[3]+=1
	return f

#main
for i in range(n):
	c(f,int(k[i]))
j+='7'*f[3]
j+='5'*(f[2]-f[3])
j+='3'*(f[1]-f[3]-f[2])
j+='2'*(f[0]-2*f[2]-f[1])

#output
print(j)