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 fact(arr):
    arr2=[]
    arr3 = []
    arr4 = []
    for valor in arr:
        if valor==2:
            arr2.append(2)
        elif valor==3:
            arr2.append(3)
        elif valor==4:
            arr2.append(2)
            arr2.append(2)
            arr2.append(3)
        elif valor==5:
            arr2.append(5)
        elif valor==6:
            arr2.append(3)
            arr2.append(5)
        elif valor==7:
            arr2.append(7)
        elif valor==8:
            arr2.append(2)
            arr2.append(2)
            arr2.append(2)
            arr2.append(7)
        elif valor==9:
            arr2.append(3)
            arr2.append(3)
            arr2.append(2)
            arr2.append(7)
        else:
            continue
    arr2.sort(reverse=True)
    arr3=map(str, arr2)
    arr4=''.join(arr3)
    return arr4

n = int(input())
val = int(input())
arr=map(int,str(val))
print(fact(arr))