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())
num = input()
a = [int(i) for i in num]
answer = []
a.sort(reverse=True)
i = 0
n7 = 0
n5 = 0
n3 = 0
n2 = 0
while (i<n and a[i]!=0 and a[i]!=1) :
    if (a[i]==9):
        n7 += 1
        n3 += 2
        n2 += 1
    elif (a[i]==8):
        n7 += 1
        n2 += 3
    elif (a[i]==7):
        n7 += 1
    elif (a[i]==6):
        n5 += 1
        n3 += 1
    elif (a[i]==5):
        n5 += 1
    elif (a[i]==4):
        n3 += 1
        n2 += 2
    elif (a[i]==3):
        n3 += 1
    else:
        n2 += 1
    i += 1
ans = "7"*n7 + "5"*n5 + "3"*n3 + "2"*n2
print(ans)
