题目描述
Problem Description
There are red and blue (six-sided) dice. When the red die is rolled, the probability of rolling an $i$ is $p_i$ percent, and when the blue die is rolled, the probability of rolling a $j$ is $q_j$ percent.
Petr and tourist are playing the following game. Both players know the probability distributions of both dice. First, Petr chooses one die of his choice (without informing tourist) and rolls it, then tells tourist the result. Next, tourist guesses the color of the chosen die. If tourist guesses the color correctly, tourist wins; otherwise, Petr wins.
Determine the probability that tourist wins when both players act optimally.
Input Format
The input is given from the standard input in the following format:
$ p_1 $ $ p_2 $ $ p_3 $ $ p_4 $ $ p_5 $ $ p_6 $ $ q_1 $ $ q_2 $ $ q_3 $ $ q_4 $ $ q_5 $ $ q_6 $
Output Format
Output the probability that tourist wins. The absolute or relative error must be no more than $ 10^{-9} $.
Sample Input and Output
Sample Input #1
25 25 25 25 0 0
0 0 0 0 50 50
Sample Output #1
1.000000000000
Sample Input #2
10 20 20 10 20 20
20 20 20 10 10 20
Sample Output #2
0.550000000000
Notes/Hints
Constraints
- $0\ \leq\ p_i,\ q_i\ \leq\ 100$
- $p_1\ +\ ...\ +\ p_6\ =\ q_1\ +\ ...\ +\ q_6\ =\ 100$
- All input values are integers.
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分