Thank you very much I couldnt figure it out.

Ahh, okay I understand it now. Thank you.

Hmm, I thought I did check that. In this array V, V[x][y] is 1 if i visited that node. And before I push node to queue I check if V of that node is 0.

I dont think i will participate in edu rounds anymore. I asked if my submission is going to be judged after it was in queue for 10 minutes. While I got the answer it was judged and the answer was "No comments". There is no need to be arrogant and in my opinion that was. Also, this would not happen if they tested the round.

Thank you very much. I wasn't aware that could be an issue.

Thank you, I understand it now.

I posted this on the main blog but I realized that maybe its better to post it here.

Can someone please explain proof of B in editorial in more detail?

In particular, I would like to know what does it mean lowerbound for maximum cost and how do we, from the observations in proof before that, conclude that this is the value of the lowerbound.

In task we need to construct the grid such that minimum cost over all paths is maximized. So I think in order to prove that some construction satisfies the requirements we need to find value C(n) such that for every placement of integers on the grid minimum cost among all paths in the grid is <= C(n). Then we need to show that for our construction minimal cost equals C(n). Am I wrong?

Can someone please explain proof of B in editorial in more detail?

In particular, I would like to know what does it mean lowerbound for maximum cost and how do we, from the observations in proof before that, conclude that this is the value of the lowerbound.

In task we need to construct the grid such that minimum cost over all paths is maximized. So I think in order to prove that some construction satisfies the requirements we need to find value C(n) such that for every placement of integers on the grid minimum cost among all paths in the grid is <= C(n). Then we need to show that for our construction minimal cost equals C(n). Am I wrong?