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())

ss = input()
result = ""

while ss != result:

    if result:
        ss = result
        result = ""
    
    res = {}
    for ch in ss:
        if ch == '0' or ch == '1':
            continue
        if ch == '4':
            if '2' in res:
                res['2'] += 2
            else:
                res['2'] = 2
            if '3' in res:
                res['3'] += 1
            else:
                res['3'] = 1
        elif ch == '6':
            if '5' in res:
                res['5'] += 1
            else:
                res['5'] = 1
            if '3' in res:
                res['3'] += 1
            else:
                res['3'] = 1
        elif ch == '8':
            if '7' in res:
                res['7'] += 1
            else:
                res['7'] = 1
            if '2' in res:
                res['2'] += 3
            else:
                res['2'] = 3
        elif ch == '9':
            if '3' in res:
                res['3'] += 2
            else:
                res['3'] = 2
            if '2' in res:
                res['2'] += 1
            else:
                res['2'] = 1
            if '7' in res:
                res['7'] += 1
            else:
                res['7'] = 1
        else:
            if ch in res:
                res[ch] += 1
            else:
                res[ch] = 1
                
    
    for d in res:
        result += d*res[d]
        
    result = ''.join(sorted(result, reverse=True))

print(result)