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>
if __name__ == "__main__":
    num = int(input())
    digits = input()
    temp = ""
    result = ""
    for i in range(0, num):
        # 0 or 1
        if (digits[i] == "0" or digits[i] == "1"):
            temp += ""
        # prime numbers
        elif (digits[i] == "2" or digits[i] == "3" or digits[i] == "5" or digits[i] == "7"):
            temp += digits[i]
        # composit numbers
        else:
            if (digits[i] == "4"):
                temp += "322"
            elif (digits[i] == "6"):
                temp += "53"
            elif (digits[i] == "8"):
                temp += "7222"
            elif (digits[i] == "9"):
                temp += "7332"
    tempStr = str(temp)
    result = ''.join(sorted(tempStr, reverse = True)) 
    print(result)