| Program | PUMP.C, PUMP.PAS, PUMP.CPP |
A particular part of the world has recently been experiencing a sudden and marked proliferation of pirate radio stations. So much so, in fact, that a group of concerned nations have asked for your assistance in pinpointing the source of the illegal transmissions. The respective governments have agreed to provide you with data from a set of mobile tracking units, each capable of determining its distance from a radio signal's point of broadcast. Armed with the information from three of these units and a two-dimensional map of the area, you are to write a program which will determine the distance and the direction of particular pirate transmitter from the nearest city in the area.
The input will consist of a two-dimensional map (using Cartesian coordinates) followed by the number of pirate signals that must be located and a corresponding number of pirate stations datasets.
In the map, the data for each city will appear on a separate line. The data for each city will consist of a 15-character name followed by the city's x- and y-coordinates and a radius. The coordinates give the city's geographical center while the radius gives the distance from the center of the city to the city limits (all cities may be considered to be circular for this problem). There will be no more than 50 cities and the last city on the map will be located at the origin (0.0, 0.0).
Following the map is a single integer (on a line by itself) which gives the number of pirate stations datasets that follow. Each pirate station dataset will consist of nine reading on a single line, separated by spaces. The first three readings correspond to mobile tracking unit A, the next three to unit B, and the last three to unit C. The first two reading in a set of three are the x- and y-coordinates where the mobile tracking unit itself is located while the third reading is the distance the unit determined itself to be from the source of the pirate radio station signal. Note that all coordinate and distance values are given in kilometers and should be stored as real numbers. The locations of the three mobile tracking units reporting information on the pirate signal will not be collinear and will always be at least 10 kilometers apart. No city will be located more than 6000 kilometers away from the city at the origin. You may assume that only valid data will be supplied.
The distance should be correct to within ±0.02 of a kilometer and output to two digits of accuracy. To determine the compass direction of the pirate transmitter from the nearest city, each of the eight principle directions should be considered to be at the center of a 45° arc in that direction. Illegal transmitters, which fall anywhere within a particular arc, are considered to be in that direction. Thus if due North is at 0°, a transmitter that was at angle between 22° and 67° (inclusive) would be considered North East of the city while a transmitter that was at angle between 68° and 112° (inclusive) would be considered East of the city. When determining the direction of the pirate transmitter, an angle should be rounded off to the nearest whole degree.
Pirate transmitters that are located inside of a city's limits should be reported as originating from that city (no distance or directional information should be output in this case). All pirate transmitter reports should be preceded by a transmitter ID number (starting with transmitter 1). Refer to the following example for the acceptable phrasing of your output.
Sample input
Pleasantville 937.8 1277.34 4.9
Avion 494.17 -483.06 12.7
Caniama -803.24 1351.68 6.53
Kingstons Falls-554.45 -300.0 1.82
Otisburg 0.0 0.0 3.6
5
286.91 1538.6 676.989 1627.84 1450.3 1026.29 1140.4 451.47 705.152
-1021.9 –1064.67 2164.66 1089.23 0.0 1796.91 993.94 –1516.17
2882.78
200.0 –295.6 824.776 –683.94 –1118.64 998.19 474.16
1729.8 2145.37
-173.21 –700.2 695.308 –202.87 191.04 971.421 1407.9 525.65
1369.38
747.02 419.61 628.79 0.0 –582.19 645.469 –987.65 294.3 1300.12
Sample output
Pirate Transmitter 1 is located 354.65 km South West of Pleasantville
Pirate Transmitter 2 is located 524.55 km South East of Caniama
Pirate Transmitter 3 is located 182.27 km North of Kingstons Falls
Pirate Transmitter 4 is located in Avion
Pirate Transmitter 5 is located 275.12 km East of Otisburg