Vanya and Brackets

题面翻译

Vanya正在认真地做他的数学作业，他碰到了一个长度为N的序列，构成序列的元素都在1~9之间，并且各个元素由加号和等号构成了一个式子。

Vanya现在需要通过增加一组小括号来改变运算顺序（运算优先级，括号>乘法>加法）。

输入格式：

一个不带括号的式子。

输出格式：

加了一组小括号后该式子能达到的最大值。

说明：

其中式子元素个数小于等于5001。

题目描述

Vanya is doing his maths homework. He has an expression of form , where $x_{1},x_{2},...,x_{n}$ are digits from $1$ to $9$ , and sign represents either a plus '+' or the multiplication sign '*'. Vanya needs to add one pair of brackets in this expression so that to maximize the value of the resulting expression.

输入格式

The first line contains expression $s$ ( $1<=|s|<=5001$ , $|s|$ is odd), its odd positions only contain digits from $1$ to $9$ , and even positions only contain signs $+$ and $*$ .

The number of signs $*$ doesn't exceed 15.

输出格式

In the first line print the maximum possible value of an expression.

样例 #1

样例输入 #1

3+5*7+8*4

样例输出 #1

303

样例 #2

样例输入 #2

2+3*5

样例输出 #2

25

样例 #3

样例输入 #3

3*4*5

样例输出 #3

60

提示

Note to the first sample test. $3+5*(7+8)*4=303$ .

Note to the second sample test. $(2+3)*5=25$ .

Note to the third sample test. $(3*4)*5=60$ (also many other variants are valid, for instance, $(3)*4*5=60$ ).