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A8081. Reflection

编程题 普及/提高-

题目描述

For each positive integer $n$ consider the integer $ψ(n)$ which is obtained from $n$ by replacing every digit $a$ in the decimal notation of $n$ with the digit $(9-a)$ . We say that $ψ(n)$ is the reflection of $n$ . For example, reflection of $192$ equals $807$ . Note that leading zeros (if any) should be omitted. So reflection of $9$ equals $0$ , reflection of $91$ equals $8$ .

Let us call the weight of the number the product of the number and its reflection. Thus, the weight of the number $10$ is equal to $10·89=890$ .

Your task is to find the maximum weight of the numbers in the given range $[l,r]$ (boundaries are included).

输入格式

Input contains two space-separated integers $l$ and $r$ ( $1<=l<=r<=10^{9}$ ) — bounds of the range.

输出格式

Output should contain single integer number: maximum value of the product $n·ψ(n)$ , where $l<=n<=r$ .

Please, do not use %lld specificator to read or write 64-bit integers in C++. It is preferred to use cout (also you may use %I64d).

输入输出样例

输入 #1
3 7
输出 #1
20
输入 #2
1 1
输出 #2
8
输入 #3
8 10
输出 #3
890

说明/提示

In the third sample weight of $8$ equals $8·1=8$ , weight of $9$ equals $9·0=0$ , weight of $10$ equals $890$ .

Thus, maximum value of the product is equal to $890$ .
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