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/env python


raw_input()
a = raw_input().strip()

occurences = [0 for i in xrange(10)]
for digit in a:
  occurences[int(digit)] += 1

occurences[7] += occurences[9]
occurences[3] += occurences[9]*2
occurences[2] += occurences[9]
occurences[9] = 0

occurences[7] += occurences[8]
occurences[2] += occurences[8]*3
occurences[8] = 0

occurences[5] += occurences[6]
occurences[3] += occurences[6]
occurences[6] = 0

occurences[3] += occurences[4]
occurences[2] += occurences[4]*2
occurences[4] = 0

output = ""
for d in reversed(xrange(2,10)):
  output += "".join([ "%d" % d for i in xrange(occurences[d])])
print output
