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(input())
digits=list(map(int,input()))
countfact={2:0,3:0,5:0,7:0}
def fact(n):
    mydict={2:0,3:0,5:0,7:0}
    factor=[i for i in range(1,n+1)]
    for val in factor:
        if val==2:
            mydict[2]+=1
        elif val==3:
            mydict[3]+=1
        elif val==4:
            mydict[2]+=2
        elif val==5:
            mydict[5]+=1
        elif val==6:
            mydict[3]+=1
            mydict[2]+=1
        elif val==7:
            mydict[7]+=1
        elif val==8:
            mydict[2]+=3
        elif val==9:
            mydict[3]+=2
    return mydict
      
            
for digit in digits:
    tmp=fact(digit)
    
    for key in tmp.keys():
        countfact[key]+=tmp[key]

while countfact[2]!=0:
    if countfact[7]!=0:
        tmp=fact(7)
        print("7",end="")
        for key in tmp.keys():
            countfact[key]-=tmp[key]
    elif countfact[5]!=0:
        tmp=fact(5)
        print("5",end="")
        for key in tmp.keys():
            countfact[key]-=tmp[key]
    elif countfact[3]!=0:
        tmp=fact(3)
        print("3",end="")
        for key in tmp.keys():
            countfact[key]-=tmp[key]
    elif countfact[2]!=0:
        tmp=fact(2)
        print("2",end="")
        for key in tmp.keys():
            countfact[key]-=tmp[key]
            
