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 math import*
def F(x):
    res=1
    for c in x:
        res=res*factorial(int(c))
    return res
def coef(x,n):
    res=0
    while n%(x**(res+1))==0:
        res=res+1
    return res

n=int(input())
x=str(input())
L=list()
n=F(x)

while (n%factorial(7))==0:
    L.append("7")
    n=n//(factorial(7))
while (n%factorial(5))==0:
    L.append("5")
    n=n//(factorial(5))
while (n%factorial(3))==0:
    L.append("3")
    n=n//(factorial(3))
while (n%factorial(2))==0:
    L.append("2")
    n=n//(factorial(2))

    
    
L.sort()
L=L[::-1]
print("".join(L))