Educational Codeforces Round 122 (Rated for Div. 2)

Solutions for Educational Codeforces Round 122 (Rated for Div. 2) (contest 1633). 3/6 problems verified against sample I/O. Difficulty range: 800-2800.

6 items

Educational Codeforces Round 122 (Rated for Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 3/6 | Rating range: 800-2800 | Time: 9m 55s

Problem Name Rating Tags Solve Time Verified
A Div. 7 800 brute-force 2m 31s ✗
B Minority 800 greedy 1m 26s ✗
C Kill the Monster 1100 brute-force, math 1m 17s ✓
D Make Them Equal 1600 dp, greedy 42s ✓
E Spanning Tree Queries 2400 binary-search, data-structures, dfs-and-similar 3m 20s ✓
F Perfect Matching 2800 data-structures, divide-and-conquer, interactive 39s ✗
Practice › Codeforces Solutions › Educational Codeforces Round 122 (Rated for Div. 2) ›

CF 1633E - Spanning Tree Queries

We are given a connected undirected graph where each edge has a fixed weight. For each query value $x$, we are allowed to pick any spanning tree of the graph.
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Practice › Codeforces Solutions › Educational Codeforces Round 122 (Rated for Div. 2) ›

CF 1633F - Perfect Matching

Working
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Practice › Codeforces Solutions › Educational Codeforces Round 122 (Rated for Div. 2) ›

CF 1633A - Div. 7

This problem is rated 3500 and its solution relies on a fairly deep structural characterization of graphs whose cycle space admits a consistent cyclic orientation.
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Practice › Codeforces Solutions › Educational Codeforces Round 122 (Rated for Div. 2) ›

CF 1633D - Make Them Equal

We are asked to start with an array of size $n$ where every element is initially 1. For each element $ai$, we can perform operations of the form $ai = ai + lfloor ai / x rfloor$, choosing $x 0$ as we like. Each element has a target value $bi$ and a reward $ci$.
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Practice › Codeforces Solutions › Educational Codeforces Round 122 (Rated for Div. 2) ›

CF 1633B - Minority

The task is to examine a binary string consisting of '0's and '1's and identify a contiguous segment where we can remove the maximum number of characters by applying a single operation.
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Practice › Codeforces Solutions › Educational Codeforces Round 122 (Rated for Div. 2) ›

CF 1633C - Kill the Monster

The problem is a turn-based combat simulation between Monocarp's character and a monster. Each has an initial health and attack.
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