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 sys
n = int(sys.stdin.readline())
num = [int(x) for x in list(sys.stdin.readline().strip()) if x != '0' and x != '1']
num.sort(reverse=True)

ans = []
for x in num:
    if x == 9:
        ans += [7,3,3,2]
    elif x == 8:
        ans += [7,2,2,2]
    elif x == 6:
        ans += [5,3]
    elif x == 4:
        ans += [3,2,2]
    elif x == 3 or x == 2 or x == 5 or x == 7:
        ans += [x]

ans.sort(reverse=True)
for x in ans:
    sys.stdout.write(str(x))