#P16873. [GKS 2022 #B] Infinity Area

    ID: 19201 远端评测题 1000ms 1024MiB 尝试: 0 已通过: 0 难度: 1 上传者: 标签>模拟数学2022Special JudgeGoogle Kick Start

[GKS 2022 #B] Infinity Area

Problem Description

Let us assume for the simplicity of this problem that the Infinity symbol is made of circles which touch externally at point SS as shown below, and let us call it the center of the infinity.

You are given three integers RR, AA, BB. You are currently at the center of the infinity. You will first start drawing the right circle with radius RR and reach again the center of infinity. After that, you start drawing the left circle with the radius equal to the radius of last circle multiplied by AA. After reaching the center of the infinity you again start drawing the right circle with radius equal to the radius of last circle divided by BB (integer divison). After reaching the center of infinity you again draw the left circle with the radius equal to the radius of last circle multiplied by AA.

:::align{center} :::

You continue to draw the left and right circles as described above until the radius of the circle to be drawn becomes zero. Calculate the sum of areas of all the circles drawn. It is guaranteed that the process will terminate after finite number of steps.

Input Format

The first line of the input gives the number of test cases, TT. TT lines follow.

Each line represents a test case and contains three integers RR, AA, BB, where RR denotes the radius of the first circle, and AA and BB are the parameters used to calculate the radii of the subsequent circles.

Output Format

For each test case, output one line containing Case #xx: yy, where xx is the test case number (starting from 11) and yy is the sum of areas of all the circles drawn until radius of the circle to be drawn becomes zero.

yy will be considered correct if it is within an absolute or relative error of 10610^{-6} of the correct answer.

2
1 3 6
5 2 5
Case #1: 31.415927
Case #2: 455.530935

Hint

In Sample Case #1\#1, you start with drawing the right circle with radius 11 unit. After reaching the center of infinity you draw the left circle with radius 1×3=31 \times 3 = 3 units. Again after reaching the center of infinity you stop drawing the right circle since the radius becomes 3/6=0\lfloor 3/6 \rfloor = 0 units. Therefore the sum of areas of the circles drawn is $\pi \times 1 \times 1 + \pi \times 3 \times 3 \approx 31.415927$.

In Sample Case #2\#2, you start with drawing the right circle with radius 55 units. After reaching the center of infinity you draw the left circle with radius 5×2=105 \times 2 = 10 units. After reaching the center of infinity you draw the right circle with radius 10/5=2\lfloor 10/5 \rfloor = 2 units. After reaching the center of infinity you draw the left circle with radius 2×2=42 \times 2 = 4 units. After reaching the center of infinity, you stop drawing since the radius of next circle becomes 4/5=0\lfloor 4/5 \rfloor = 0 units. Therefore the sum of areas of the circles drawn is $\pi \times 5 \times 5 + \pi \times 10 \times 10 + \pi \times 2 \times 2 + \pi \times 4 \times 4 \approx 455.530935$.

Limits

Test Set 11

1T1001 \le T \le 100

1R1051 \le R \le 10^5

1A5001 \le A \le 500

2×AB10002 \times A \le B \le 1000