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 f(x):
    if(x==1 or x==0):
        return
    else:
        if(x==2 or x==3 or x==5 or x==7):
            b.append(x)
        elif(x==4):
            b.append(2)
            b.append(2)
            b.append(3)
        elif(x==6):
            b.append(3)
            b.append(5)
        elif(x==8):
            b.append(2)
            b.append(2)
            b.append(2)
            b.append(7)
        elif(x==9):
            b.append(2)
            b.append(3)
            b.append(3)
            b.append(7)

b=[]
n=int(input())
a=input()
for i in range(n):
    f(int(a[i]))
b.sort(reverse= True)
print("".join(str(x) for x in b))
"""
2 = 2
3 = 3
4 = 322
5 = 5
6 = 53
7 = 7
8 = 7222
9 = 7332
"""
