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 factorial
from sys import stdin as GOD

def get_fact(x):
    ans = []
    while x > 0:
        temp = x % 10
        if temp == 4:
            ans.append(3)
            ans.append(2)
            ans.append(2)
        elif temp == 6:
            ans.append(5)
            ans.append(3)
        elif temp == 8:
            ans.append(7)
            ans.append(2)
            ans.append(2)
            ans.append(2)
        elif temp == 9:
            ans.append(7)
            ans.append(3)
            ans.append(3)
            ans.append(2)
        elif temp > 1: ans.append(temp)
        x /= 10
    ans.sort()
    ans.reverse()
    print "".join(map(str, ans))

N = int(GOD.readline())
num = int(GOD.readline())
get_fact(num)