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>
#!/usr/bin/env python3
n = int(input())
a = input()
nb_digits = [0] * 10
for x in range(n):
    if a[x]=="0":
        continue
    elif a[x]=="1":
        continue
    elif a[x]=="2":
        nb_digits[2] += 1
    elif a[x]=="3":
        nb_digits[3] += 1
    elif a[x]=="4":
        nb_digits[2] += 2
        nb_digits[3] += 1
    elif a[x]=="5":
        nb_digits[5] += 1
    elif a[x]=="6":
        nb_digits[3] += 1
        nb_digits[5] += 1
    elif a[x]=="7":
        nb_digits[7] += 1
    elif a[x]=="8":
        nb_digits[2] += 3
        nb_digits[7] += 1
    elif a[x]=="9":
        nb_digits[2] += 1
        nb_digits[3] += 2
        nb_digits[7] += 1
nb_output = ""

for x in reversed(range(2, 8)):
    nb_output += str(x) * nb_digits[x]
print(nb_output)
