I’m having a real hard time for solving this one.
The really obvious solution is too slow to compute the result.
I implemented some kind of a dichotomic search, but it does not seems to validate in time. I pass every “simple test” (up until the 6th test) with no problems, but then, I don’t have enough moves to solve the two last tests.

I’d love to explain my current algorithm, but I’m afraid of giving too much information and spoiling the fun for the others

I didn’t know there were review on the challenges ont he blog !
It actually gives a solution really close to mine, my way of dividing space was not exactly the same though. I think this is where the problem lies !

Btw I need help on this. I can pass everything except the last one.
Ive used a board to store the area that is to be searched .Something like : char board[10000][10000];
But the problem is that I cant iterate a 8000 X 8000 board under 100 ms.

So I put a condition

if( w>=5000)
w/=4;
if( h>=5000)
h/=4;

And luckily for me the bomb was in the top corner So I kinda temporarily solved it.
But I still want to learn how to really solve it. I read the blog and they dont really explain their approach properly and I dint understand that also.

My approach is quite difficult to implement, but it’s easy to understand:

Quick Observation:
Our blue/active area (where the bomb can be installed) is always convex polygon

So what we’re gonna do?

Let’s select point randomly where we want to go

Divide active polygon into two polygons along the perpendicular line to move vector (one of them will be next active polygon) and compute area each of them. (area1 and area2)

Remember value of min(area1, area2) and store the point with the largest one.

Repeat all until end of time (for me it was about ~25k iterations)

So, in a nutshell, we’re looking for a point that will slice active area into two equal halves.

Some improvements:

We can improve process of drawing new points - we can randomly choose point from ACTIVE AREA and compute reflection of current point from chosen one (chosen point will be on the line that slices polygon), but we have to care for cases when reflection point is outside of allowed rectangle).

We can add some heuristics to process of picking points - for example: distance to centroid of polygon.