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>
a=[[0,0,0,0],[0,0,0,0],
   [1,0,0,0],[1,1,0,0],
   [3,1,0,0],[3,1,1,0],
   [4,2,1,0],[4,2,1,1],
   [7,2,1,1],[7,4,1,1]]
n=input()
s=input()
s=s.replace("\r","")
k2=0;k3=0;k5=0;k7=0;
for x in s:
    k2+=a[int(x)][0]
    k3+=a[int(x)][1]
    k5+=a[int(x)][2]
    k7+=a[int(x)][3]
s=""
while k7>0:
    s+="7"
    k7-=a[7][3]
    k5-=a[7][2]
    k3-=a[7][1]
    k2-=a[7][0]    
while k5>0:
    s+="5"
    k5-=a[5][2]
    k3-=a[5][1]
    k2-=a[5][0]
while k3>0:
    s+="3"
    k3-=a[3][1]
    k2-=a[3][0]
while k2>0:
    s+="2"
    k2-=1
print(s)
