Example 7: Distance Between the Two Points

Problem

Write a program that receives latitude values (L1, L2) and longitude (G1, G2) of two places on Earth, in degrees, and returns the distance between them.

The formula for distance in nautical miles is:

D = 3963 * $acos$ ( $\sin L1 * \sin L2$ + $\cos L1*\cos L2$ * $\cos$( G2–G1 ))