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>
var n = Number(readline());
var a = readline();
a = a.replace(/0/g, '').replace(/1/g, '');
var b = [];
for (var i = 0; i < a.length; i++) {
	if (a[i] === '4') {
		b.push('3');
		b.push('2');
		b.push('2');
	} else if (a[i] === '6') {
		b.push('5');
		b.push('3');
	} else if (a[i] === '8') {
		for (var j = 0; j < 3; j++) {
			b.push('2');
		}
		b.push('7');
	} else if (a[i] === '9') {
		b.push('3');
		b.push('3');
		b.push('2');
		b.push('7');
	} else {
		b.push(a[i]);
	}
}

b.sort(function(x, y) {return x - y;}).reverse();
print(b.join(''));