2663Escape from the Darkness

2663   Escape from the Darkness

题目描述

     Xiao Ming, a high school student, learnt blackbody radiation from the physics class. The black body on the book is indicated approximately by black body cavity as below: 

 from the small hole if total reflection occurs on the surface of the cavity.

    Assuming in the two-dimensional coordinates, the center of the oval is at origin, and the vertexes of it is respectively (a, 0), (-a, 0), (0, b), (0, -b). There is a small hole at (a/2,sqrt(3)*b/2) (whose areas can be ignored). A beam of light (whose diameter can be ignored) shoot into the oval through the small hole. The direction of the light is (-1, 0). Assuming the light totally mirror reflects on the surface of the oval, the question is how many times can the light reflect before shooting out through the small hole. (If a point is away from the small hole less than 0.01, we think light shoot out from that point.)

输入格式:

     The first line is a positive integer T (1 <= T <= 55) which indicates the numbers of the test cases. Then flowing next T lines, there are two positive integer a, b (1 <= b<= a<= 10) in each line as a group of cases. 

输出格式:

     The output of each case is one line with a positive integer which indicates the times of reflects. 

输入样例 复制
1
1 1
输出样例 复制
5

说明

 The path of the light in the sample is looked as the picture shows. The light reflected five times.

1
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时空限制1000ms/1280mb
题目来源数据结构实验与竞赛训练
评测方式在线评测
题目类型
难        度