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 collections import deque
from math import gcd,sqrt,log
def mi():return map(int,input().split())
def li():return list(mi())
def ii():return int(input())
a=[0]*10
a[0]=1
for i in range(1,10):
    a[i]=i*a[i-1]
b=['0']*10
b[2]='2'
b[3]='3'
b[4]='322'
b[5]='5'
b[6]='53'
b[7]="7"
b[8]="7222"
b[9]='7332'
c=[7,9,8,5,6,3,4,2]
n=ii()
s=input()
b1=[0]*10
for i in s:
    b1[int(i)]+=1
s1=""
for i in range(2,10):
    s1+=b[i]*b1[i]
s1=list(s1)
s1.sort(reverse=True)
print("".join(s1))