编程介的小学生 2017-08-30 13:03 采纳率: 20.5%
浏览 761
已采纳

Mobile Positioning

Mobile positioning is a technology used by telecommunication companies to approximate where a mobile phone is. Although it is not that accurate than some alternatives, such as GPS, it is quick and costs less. In this problem, we consider a special version of mobile positioning with two base stations used.

Mobile Positioning

The graph shows how mobile positioning works. P1(x1, y1) and P2(x2, y2) are two base stations communicating with mobile phones. Someone is walking from Point A to Point C in a straight line with constant speed. The positioning has 5 steps:

At Point A, his mobile phone emits a signal to base station P1.
After time t1, the base station P1 receives the signal and echoes back immediately.
After time t2, the mobile phone gets the signal from the base station P1 at Point B, and then transmits a new signal to the base station P2 immediately.
The signal transfers for time t3 and arrives at the base station P2, and then a new signal by P2 is sent back immediately.
After time t4, the mobile phone receives the signal at Point C.
It is well known that signals go off in all directions, like a series of circles that shares a same center. With the speed of signal v given, please find out the coordinates of ALL possible Point A.

Input

The input contains no more than 30 cases. Each case contains two lines. The first line is 4 numbers x1, y1, x2, y2 (-10000 < x1, y1, x2, y2 < 10000). The second line has 5 numbers, t1, t2, t3, t4, v (0 ≤ t1, t2, t3, t4 < 10000, 0 < v < 10000).

Proceed to the end of file.

Output

For each case, output a single line contains the number of possible Point A, then n lines of the coordinates in the form "x y" in ascending order. Keep two digits after the decimal point. If the number of possible Point A is infinite, simply output -1. You can assume that there is at least one possible Point A.

Sample Input

0 12 16 6
6 10 3 5 2
Sample Output

4
0.00 0.00
7.89 21.04
11.08 7.38
11.38 8.19

  • 写回答

1条回答 默认 最新

  • threenewbee 2017-09-14 16:19
    关注
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论

报告相同问题?

悬赏问题

  • ¥15 kafka 分区副本增加会导致消息丢失或者不可用吗?
  • ¥15 微信公众号自制会员卡没有收款渠道啊
  • ¥15 stable diffusion
  • ¥100 Jenkins自动化部署—悬赏100元
  • ¥15 关于#python#的问题:求帮写python代码
  • ¥20 MATLAB画图图形出现上下震荡的线条
  • ¥15 关于#windows#的问题:怎么用WIN 11系统的电脑 克隆WIN NT3.51-4.0系统的硬盘
  • ¥15 perl MISA分析p3_in脚本出错
  • ¥15 k8s部署jupyterlab,jupyterlab保存不了文件
  • ¥15 ubuntu虚拟机打包apk错误