# Can anyone help me with Protecting Sheep from Dementia 2012 - IIT Mandi Contest?

Hello friends can someone tell me how to approach this problem ??

It is a problem on convex-hull.

First try solving this problem. You will get the basic idea, and then you can easily implement the algorithm in this problem.

Jarvis March Algorithm is sufficient for the given constraints.

In this particular question, it is mentioned that “each of the sheep is inside a square of side 2 units” && “Note that the orientation of all of these squares is identical, and the coordinate system has been selected so that each of the sides are parallel to one of the axes”, which essentially means that, for each sheep co-ord. (x, y), you need to consider 4 co-ord.s, namely (x+1, y+1), (x+1, y-1), (x-1, y+1), (x-1, y-1) in your convex-hull algorithm.

If you are still not able to solve it, try to understand this code by @madguy02 .

Video Tutorial of the algorithm can be found here.

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thankyou. Now i got it:)