## 1990A — Submission Bait

## 1990B — Array Craft

## 1990C — Mad MAD Sum

## 1990D — Grid Puzzle

## 1990E2 — Catch the Mole(Hard Version)

Not a formal proof! (please explain the formal proof of the algorithm in the comment section if you know that)

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Not a formal proof! (please explain the formal proof of the algorithm in the comment section if you know that)

Tutorial of Codeforces Round 960 (Div. 2)

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Congrats for reaching 10K dude <3

Thank you bro <3

Why video editorial?

text editorials take time to complete , besides Shayan does some clean coding too , so its nice in the mean time.

The authors will prepare the text editorial.

Can someone please explain problem D? I understood everything in the editorial up until adding the second dimension to the dp array. I don't get that part, why do we add dp[i][j] where j can be {0,1,2,3}? And is there a way to solve this without adding this second dimension?

Problem D can be solved using greedy: https://codeforces.com/contest/1990/submission/271628945

The "A.Submission Bait" problem really lives up to its name

Problem D greedy solution with just 2 variables and one for loop: 271663296

Idea/SolutionAlways color a 2x2 grid if the remaining area on a_i after a_i-1 is colored is <= 2, otherwise it is always optimal to color the entire row.

Same idea here, but tracking column indices instead: 271665697

trash ass solution. clearly codeforces is not for u lil bluh

What didn't you like about it? Maybe we can improve if u tell us so.

Please add Russian subtitles to the video

Shayan, could you please answer this.... for Problem D, dp[i][j], j={0,1,2,3} what is the j here ? , is it {00,01,10,11} where each boolean value tell us about the use of the 1st and 2nd 2x2 block in i_th row ?

Exactly. It shows the 4 possible ways for the 1st and the 2nd 2*2 block in the row number i.

why is it getting downvoted?