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>
n=int(raw_input())
a=int(raw_input())
f=[0]*20
f[0]=1
for i in xrange(1,20):
    f[i] = f[i-1] * i
    #print f[i]

b = a
k = 1
while b > 0:
    k = k * f[b%10]
    b/=10
#print b
ans=0
p=[7,5,3,2]
for i in xrange(4):
    t=p[i];
    while k%t==0 :
        k/=f[t]
        ans=ans*10+t
        #print k
    if(k==1):
        break;
print ans
            
        
    
'''
15
012345781234578
'''
