CPC '21 Contest 1 P3 - AQT and Circles
View as PDFAQT is studying circles and he has encountered the following problem. Two circles  and 
 have their centres located at 
 on a coordinate plane. Circle 
 and 
 have radii 
 and 
 
, respectively. AQT decides to add another circle 
 with radius 
 
 and a centre that is located at 
, where 
 and 
 are real numbers. The location of circle 
 is random but it follows the condition that it is completely inside circle 
. Formally, 
. A position of circle 
 is called valid if the circumference of circle 
 has 
 intersection points with the circumference of circle 
. AQT wants to know the probability that the position of circle 
 is valid. AQT is given 
 of these problems. Can you help AQT solve all of them?
Constraints
In all subtasks,
It is guaranteed that , 
, and 
 are integers.
Subtask 1 [10%]
Subtask 2 [15%]
Subtask 3 [75%]
No additional constraints.
Input Specification
The first line contains , the number of problems you need to help AQT solve.
The next  lines each contain the radii of the three circles: 
, 
, and 
.
Output Specification
Output  lines. In the 
-th line, output the answer to the 
-th problem. Your answer will be considered correct if it differs from the correct answer by at most 
.
Sample Input
2
2 3 1
5 10 2
Sample Output
0.25
0.375
Explanation
For the first test case, circle  and 
 are represented by the blue circle and the red circle, respectively.
The green circles represent possible valid positions for circle 
.
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