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())
k = []
t = list(map(int, input().rstrip()))
for i in range(n):
    if t[i] == 2:
        k.append(2)
    elif t[i] == 3:
        k.append(3)
    elif t[i] == 4:
        k.append(3)
        k.append(2)
        k.append(2)
    elif t[i] == 5:
        k.append(5)
    elif t[i] == 6:
        k.append(5)
        k.append(3)
    
    elif t[i] == 7:
        k.append(7)
    elif t[i] == 8:
        k.append(7)
        k.append(2)
        k.append(2)
        k.append(2)
    elif t[i] ==9:
        k.append(7)
        k.append(3)
        k.append(3)
        k.append(2)
    else:
        a =0
k.sort()
k.reverse()
for j in range(len(k)):
    print(k[j],end="")