Problem A
Time Limit : 3000/1000ms (Java/Other) Memory Limit : 65535/32768K (Java/Other)
Total Submission(s) : 29 Accepted Submission(s) : 10
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Problem Description
It is said that Wechat(weixin) will release a new game called “tian tian fei che”. It is also said that in this game, when the whole run time is X second, the oil you spend is A-B*X (50>A>0,50>B>0)
The price of this oil is B^X (we account it in the end)
So it seems that you will cost X*(A-B*X)*B^X in this journey.
One day tu hao began to paly this game. But he want to dispaly the money he cost in the “circle of freind” on Wechat. He want to show that he spend the most money. So how can he spend the most money. Can you help him?(X could not be an integer)
The price of this oil is B^X (we account it in the end)
So it seems that you will cost X*(A-B*X)*B^X in this journey.
One day tu hao began to paly this game. But he want to dispaly the money he cost in the “circle of freind” on Wechat. He want to show that he spend the most money. So how can he spend the most money. Can you help him?(X could not be an integer)
Input
There will be many cases. Each case will have two integers A and B indicating the parameters in the formula.
Output
Out put the maximum cost in the journey. rounded to 3 digitsafter decimal point.
Sample Input
25 20
Sample Output
100.000