Drazil is playing a math game with Varda.

Let's define <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> for positive integer *x* as a product of factorials of its digits. For example, <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/6784d861d9a724d0aeddefcb00b7d0c3442ae586.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

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. <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> = <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/aa57e017a6c74d06b0a54bc47e3f6990e5af38c1.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

Help friends find such number.
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.
import heapq
from collections import *
import math
def fact(n):
    fact = 1
    for j in range(1, int(n) + 1):
        fact = fact * j
    return fact

def solve():

    n = int(input())
    s = input()
    a = [0, 0, 2, 3, 223, 5, 35, 2227, 2337]
    ans = []
    for i in range(n):
        if int(s[i])>1:
            ans.append(a[int(s[i])])
    ans.sort(reverse=True)
    s = ""
    for i in ans:
        s+=str(i)
    s = list(s)
    s.sort(reverse=True)
    t = ""
    for i in s:
        t+=str(i)
    print(t)

# t = int(input())
# for _ in range(t):
#     solve()
solve()
