How do one decide the direction in Where do I Turn?

Revision en2, by ganesh_6, 2022-03-20 12:59:03

I was solving the question http://codeforces.me/contest/227/problem/A. If the cross product is zero then obviously they are collinear since sin(x)=0 if x=2*n*PI. However, how do they decide if it is Left or Right based on the value of cross-product i.e; x1*y2-x2*y1. Please demystify this for me. Am I missing any fundamentals?

C++
Tags geometry

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en2 English ganesh_6 2022-03-20 12:59:03 80
en1 English ganesh_6 2022-03-20 11:03:25 936 Initial revision (published)