Codeforces Round 939 (Div. 2)

7 problems from Codeforces Round 939 (Div. 2) (contest 1956), difficulty 800-3000. 3/7 solutions verified against sample I/O.

7 items

Codeforces Round 939 (Div. 2)

Div. 2 | 7 problems | 3/7 verified | Difficulty 800-3000 | 7m 40s

# Problem Rating Tags Accepted Time ✓
A Nene's Game 800 binary-search, brute-force, data-structures 24,189 1m 6s
B Nene and the Card Game 800 games, greedy 22,927 53s ✓
C Nene's Magical Matrix 1600 constructive-algorithms, greedy, math 15,142 57s ✓
D Nene and the Mex Operator 2000 bitmasks, brute-force, constructive-algorithms 4,779 1m 10s ✓
E1 Nene vs. Monsters (Easy Version) 2500 brute-force, implementation, math 1,671 1m 15s
E2 Nene vs. Monsters (Hard Version) 2700 brute-force, greedy, implementation 1,130 1m 1s
F Nene and the Passing Game 3000 constructive-algorithms, data-structures, dsu 482 1m 18s
Practice › Codeforces Solutions › Codeforces Round 939 (Div. 2) ›

CF 1956A - Nene's Game

We are given an increasing list of positions, and a process that repeatedly deletes players from a line. In each round, we look at the current lineup and try to remove the players standing at positions $a1, a2, ldots, ak$.
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CF 1956B - Nene and the Card Game

We are given a multiset of $2n$ cards, where every number from $1$ to $n$ appears exactly twice in total. These cards are split evenly between two players, you and Nene, so each of you holds $n$ cards.
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CF 1956C - Nene's Magical Matrix

We are given a square matrix of size $n times n$ initially filled with zeroes. Nene can perform two types of operations: either set an entire row to a permutation of $1$ through $n$ or set an entire column to such a permutation.
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CF 1956D - Nene and the Mex Operator

We are given a short array of length at most 18. The only allowed move is to pick a contiguous segment, compute the mex of that segment, and overwrite the entire segment with that mex value.
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Practice › Codeforces Solutions › Codeforces Round 939 (Div. 2) ›

CF 1956E1 - Nene vs. Monsters (Easy Version)

We are given a circle of n monsters, each with an initial energy level ai. They are numbered from 1 to n, and each monster attacks its clockwise neighbor simultaneously in a single round.
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Practice › Codeforces Solutions › Codeforces Round 939 (Div. 2) ›

CF 1956E2 - Nene vs. Monsters (Hard Version)

We are given a circle of monsters, each with an energy level. The monsters attack their neighbor in a fixed clockwise order: monster 1 attacks monster 2, monster 2 attacks monster 3, and so on, with the last monster attacking the first.
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Practice › Codeforces Solutions › Codeforces Round 939 (Div. 2) ›

CF 1956F - Nene and the Passing Game

We are given a sequence of basketball players, each with a passing range expressed as an interval $[li, ri]$. The players are numbered from 1 to $n$.
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