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>
def main():
    from sys import stdin, stdout

    # stdin = open("in.txt", "r")

    num = stdin.read().split()[1]

    ans = []

    for d in num:
        if d == '2':
            ans.append('2')
        elif d == '3':
            ans.append('3')
        elif d == '4':
            ans.append('3')
            ans.append('2')
            ans.append('2')
        elif d == '5':
            ans.append('5')
        elif d == '6':
            ans.append('5')
            ans.append('3')
        elif d == '7':
            ans.append('7')
        elif d == '8':
            ans.append('7')
            ans.append('2')
            ans.append('2')
            ans.append('2')
        elif d == '9':
            ans.append('7')
            ans.append('3')
            ans.append('3')
            ans.append('2')

    ans.sort(reverse=True)

    stdout.write(''.join(ans))


if __name__ == '__main__':
    main()

     		 	 		 	 	     	 	    			