Codeforces Round 994 (Div. 2)

6 problems from Codeforces Round 994 (Div. 2) (contest 2049), difficulty 800-2700. 0/6 solutions verified against sample I/O.

6 items

Codeforces Round 994 (Div. 2)

Div. 2 | 6 problems | 0/6 verified | Difficulty 800-2700 | 11m 24s

#	Problem	Rating	Tags	Accepted	Time
A	MEX Destruction	800	greedy, implementation	24,126	1m 44s
B	pspspsps	1300	brute-force, constructive-algorithms, graph-matchings	18,923	2m 13s
C	MEX Cycle	1500	brute-force, constructive-algorithms, greedy	13,637	1m 39s
D	Shift + Esc	1900	brute-force, dp	6,014	1m 54s
E	Broken Queries	2400	binary-search, bitmasks, brute-force	1,591	1m 52s
F	MEX OR Mania	2700	bitmasks, brute-force, data-structures	581	2m 2s

Practice › Codeforces Solutions › Codeforces Round 994 (Div. 2) ›

CF 2049F - MEX OR Mania

The task asks us to process a sequence of integers and repeatedly answer the following: after each update to an element, what is the length of the longest contiguous subarray for which the MEX minus the bitwise OR of all elements equals exactly one.

Practice › Codeforces Solutions › Codeforces Round 994 (Div. 2) ›

CF 2049E - Broken Queries

We are asked to determine a hidden integer $k$ in an interactive setting, where $k$ controls the behavior of a device that responds to range queries on a hidden binary array of length $n$. The array contains exactly one 1 and all other elements are 0.

Practice › Codeforces Solutions › Codeforces Round 994 (Div. 2) ›

CF 2049D - Shift + Esc

We are given a grid of integers with $n$ rows and $m$ columns. Each cell contains a non-negative integer. We start at the top-left corner and want to reach the bottom-right corner, moving only right or down.

Practice › Codeforces Solutions › Codeforces Round 994 (Div. 2) ›

CF 2049B - pspspsps

I can't reliably diagnose the algorithmic bug from the information provided. The sample input/output pair is not enough to reconstruct the original problem, and the fact that the program now produces a blank output instead of a traceback suggests that we're no longer looking…

Practice › Codeforces Solutions › Codeforces Round 994 (Div. 2) ›

CF 2049A - MEX Destruction

We are given several independent test cases. In each test case, there is an array of small integers. The allowed operation takes any contiguous segment of the array, computes the MEX of the values inside that segment, and replaces the entire segment with that single value.

Practice › Codeforces Solutions › Codeforces Round 994 (Div. 2) ›

CF 2049C - MEX Cycle

We are given a circular arrangement of $n$ nodes, each representing a dragon. Every dragon is connected to its two neighbors in the circle, and additionally there is one extra undirected edge between two specified nodes $x$ and $y$.