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>
import math


n = int(input())
l = input()
ans = []
for i in range(len(l)):
    if int(l[i]) % 2 == 0 and int(l[i]) != 0:
        if int(l[i]) == 2:
            ans.append(2)
        else:
            if int(l[i]) == 4:
                ans.append(2)
                ans.append(2)
                ans.append(3)
            else:
                if int(l[i]) == 8:
                    ans.append(2)
                    ans.append(2)
                    ans.append(2)
                    ans.append(7)
                else:
                    if int(l[i]) == 6:
                        ans.append(3)
                        ans.append(5)
    else:
        if int(l[i]) == 1 or int(l[i]) == 0:
            pass
        else:
            if int(l[i]) == 9:
                ans.append(7)
                ans.append(2)
                ans.append(3)
                ans.append(3)
            else:
                ans.append(int(l[i]))



result = ""
ans = sorted(ans)
for i in range(len(ans)):
    result += str(ans[len(ans) - 1 - i])

print(result)