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 sys import stdin, stdout
import math

n = int(stdin.readline())
s = stdin.readline()[:-1]

a2 = 0
a3 = 0
a5 = 0
a7 = 0

for d in s:
    for x in range(2,int(d)+1):
        if x==2:
            a2+=1
        if x==3:
            a3+=1
        if x==4:
            a2+=2
        if x==5:
            a5+=1
        if x==6:
            a2+=1
            a3+=1
        if x==7:
            a7+=1
        if x==8:
            a2+=3
        if x==9:
            a3+=2
res = ''
for i in range(a7):
    res += '7'
    a2 -= 4
    a3 -= 2
    a5 -= 1
    #print(a2,a3,a5,a7)
for i in range(a5):
    res += '5'
    a2 -= 3
    a3 -= 1
    #print(a2,a3,a5,a7)
for i in range(a3):
    res += '3'
    a2 -= 1
    #print(a2,a3,a5,a7)
for i in range(a2):
    res += '2'
    #print(a2,a3,a5,a7)
print(res)
