Problem E: Tunnelling the Earth
There are different methods of transporting people from
place to place: cars, bikes, boats, trains, planes, etc.
For very long distances, people generally fly in a plane.
But this has the disadvantage that the plane must fly around
the curved surface of the earth. A distance travelled would
be shorter if the traveller followed a straight line from
one point to the other through a tunnel through the earth.
For example, travelling from Waterloo to Cairo requires a
distance of 9293521 metres following the great circle route around
the earth, but only 8491188 metres following the straight line
through the earth.
For this problem, assume that the earth is a perfect sphere with
radius of 6371009 metres.
The first line of input contains a single integer, the number of test
cases to follow. Each test case is one line
containing four floating point numbers:
the latitude and longitude of the origin of the trip,
followed by the latitude and longitude of the destination of
the trip. All of these measurements are in degrees.
Positive numbers indicate North latitude and East longitude,
while negative numbers indicate South latitude and West longitude.
43.466667 -80.516667 30.058056 31.228889
For each test case, output a line containing a single integer, the
difference in the distance between the two points following the great
circle route around the surface of the earth and following the straight
line through the earth, in metres. Round the difference of the
distances to the nearest integer number of metres.
Output for Sample Input
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