题目描述
Run, Twins
E869120 You started running from home to school at a speed of $ P $ meters per minute.
square1001 noticed E869120's forgotten thing $ A $ minutes after E869120 left home and chased at $ Q $ meters per minute.
Then E869120 noticed something left behind $ B $ minutes after E869120 left home and turned back at $ R $ meters per minute.
E869120 How many minutes after you leave home will the twins meet?
However, E869120 and square1001 will not meet by $ B $ minutes.
Also, assume that there is only one road from E869120 and square1001's house to school, and there are no shortcuts or alternatives.
input
Input is given from standard input in the following format.
$ A $ $ B $
$ P $ $ Q $ $ R $
output
Output the time from when E869120 left home to when E869120 and square1001 meet.
However, insert a line break at the end.
If the absolute error or relative error from the assumed answer is within $ 10 ^ {-3} $, it will be treated as a correct answer.
Constraint
- $1 \ leq A \ leq B \ leq 100$
- $1 \ leq Q \ leq P \ leq 100$
- $1 \ leq R \ leq 100$
- All inputs are integers.
Input example 1
14 86
9 1 20
Output example 1
119.428571428571
Input example 2
14
15 9 2
Output example 2
7.000000000000
Input example 3
67 87
7 4 51
Output example 3
96.618181818182
Example
Input
14 86
9 1 20
Output
119.428571428571
输入格式
见题面
输出格式
见题面