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/pypy3

from sys import stdin,stderr

def readInts(): return map(int,stdin.readline().strip().split())
def print_err(*args,**kwargs): print(*args,file=stderr,**kwargs)
    
def solve(a):
    fs = {0:[],1:[],2: [2], 3: [3], 4:[3,2,2],
          5:[5],6:[5,3],7:[7],8:[7,2,2,2],9:[7,2,3,3] }
    factors = []
    while a>0:
        factors += fs[a%10]
        a//=10
    factors.sort()
    factors.reverse()
    return "".join(map(str,factors))

def run():
    n, = readInts()
    a, = readInts()
    print(solve(a))
        
run()
