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>
n = int(input())
num = input().strip()

# 2-9
# 2, 3, 5, 7 not reducible
# 4 -> 2!(2) * 3!(1)
# 6 -> 3! 5! 
# 8 -> 2!(3) * 7!
# 9 -> 3^ 2 * 8! = 3!(2) * 2!(1) * 7!(1)

ans = ''

for n in num:
    n = int(n)
    ta = ''
    if n in [2, 3, 5, 7]:
        ta = str(n)
    elif n == 4:
        ta = '223'
    elif n == 6:
        ta = '35'
    elif n == 8:
        ta = '2227'
    elif n == 9:
        ta = '3327'
    else:
        # print(f'no match for {n}')
        continue
        
    ans += ta

ans = sorted(ans)
print(''.join(reversed(ans)))


