Seeking Help in Painting the Barn

[Yash_Aggarwal]

I needed help with the following problem :
Problem Link

Solution Link
In the editorial of this problem, it is given that we are adding at the starting and the ending point of the corners (x1, y1) and (x2, y2) whereas decrement the other 2 corners. Could someone please explain the logic behind this?

Thanks.

[pavanscoding]

Problem statement confusion (2019 Feb Gold)

In the problem Painting the Barn, the sample test cases produce the following (truncated) grid (number in the cell represents the number of coats of paint applied): [image] Now, we can paint regions (2,7)\rarr (8,7) and (8,2)\rarr (8,6) to give a total of 33 cells with 2 coats of paint. However, the answer states 26. What is the mistake in my diagram or notation?

It’s the same concept. Basically, the points given are coordinates.