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>
from collections import defaultdict
n=int(input())
a=input()
hashmap=defaultdict(int)
for i in a:
    for j in range(2,int(i)+1):
        hashmap[j]+=1
# print(hashmap)
to_delete=[]
for k in hashmap:
    flag=0
    for j in [2,3,5,7]:
        if int(k)%j==0 and k not in [2,3,5,7]:
            if k//j//j==j:
                hashmap[j] += hashmap[k] * 3
            elif k//j==j:
                hashmap[j]+=hashmap[k]*2
            else:
                hashmap[j] += hashmap[k]
            flag=1
    if flag==1 and k not in [2,3,5,7]:
        to_delete.append(k)
for i in to_delete:
    del hashmap[i]
# print(hashmap)
prime={2:{2:1},3:{3:1,2:1},4:{2:3,3:1},5:{5:1,2:3,3:1},7:{3:2,2:4,5:1}}
keys=sorted(list(hashmap.keys()),reverse=True)
answer=''
# print(hashmap)
for key in keys:
    temp=hashmap[key]
    answer+=str(key)*hashmap[key]
    for j in prime[key]:
        # print(j)
        # print(hashmap[j])
        hashmap[j]-=prime[key][j]*temp

        # print(hashmap)/
print(answer)

