题目描述
Drazil is playing a math game with Varda.
Let's define $$\mathbf{F}(x)$$ for positive integer x as a product of factorials of its digits. For example, $$F(135) = 1! * 3! * 5! = 720$$.
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:
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x doesn't contain neither digit 0 nor digit 1.
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$$\mathbf{F}(x)$$ = $$\mathbf{F}(a)$$.
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.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分
样例输入
样例输出
提示
In the first case, $$F(1234) = 1! * 2! * 3! * 4! = 288 = F(3322)$$