Comments

good one!

Nice one, will def try it

Pretty useful, thanks!

On ok12Editorial of ICPC de Tryst 2026, 6 months ago
+6

Both the orderings are incorrect, my ordering fails the case given by chicubed

In your ordering, the first 6 queries would be:

(N-1) (N+1) ( N ) (N-2) ( N ) (N-1)

The position of X can be:

(N-3) (N-2) (N-1) ( N ) (N+1) (N+2)

After this we can keep moving X forward.

I think the problem just can't be solved using such orderings.

On ok12Editorial of ICPC de Tryst 2026, 6 months ago
0

Damn we didn't thought about that, the interactor missed this as well leading to our incorrect solution getting AC

Submission link

On ok12Editorial of ICPC de Tryst 2026, 6 months ago
+5

Edit: The solution turned out to be wrong

An alternative solution to G:

While n>3, we can query {n , n-1 , n+1}, if all these are 0 then it implies that X in range [1,n-1]
When n==3, we can ask the following queries: {2, 4, 3, 2} and we will determine X.

The total number of queries is 3*(n-3) + 4

+7

A lot of people cheated in D2 E as well, putting some of those here

Link 1

Link 2

Link 3

Link 4

Even there solutions are quite similar, looks like they both copied from the same source

Really enjoyed the contest, especially the C problem

On Casual_WTutorial for AlgoArena 2026, 7 months ago
+1

I ran the editorial solution on the testcase in custom invocation in C++ 17, for that it ran in 3000ms, however for C++ 20 it ran in 800 ms, i don't really know why is that the case

On Casual_WTutorial for AlgoArena 2026, 7 months ago
0

For G the testcase

2

1 100

1 100000

This 1000 times would lead to TLE and is a valid testcase

orz

bilkul sleepyAdarsh bhai XD