Educational Codeforces Round 95 (Rated for Div. 2)

Solutions for Educational Codeforces Round 95 (Rated for Div. 2) (contest 1418). 4/7 problems verified against sample I/O. Difficulty range: 1000-3000.

7 items

Educational Codeforces Round 95 (Rated for Div. 2)

Type: Div. 2 | Problems: 7 | Verified: 4/7 | Rating range: 1000-3000 | Time: 12m 59s

Problem Name Rating Tags Solve Time Verified
A Buying Torches 1000 math 1m 11s ✓
B Negative Prefixes 1300 greedy, sortings 2m ✗
C Mortal Kombat Tower 1500 dp, graphs, greedy 1m 31s ✓
D Trash Problem 2100 data-structures, implementation 4m 23s ✗
E Expected Damage 2400 binary-search, combinatorics, probabilities 1m 24s ✓
F Equal Product 3000 data-structures, math, number-theory 2m 2s ✓
G Three Occurrences 2500 data-structures, divide-and-conquer, hashing 28s ✗
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418D - Trash Problem

Thank you. I have carefully traced the bug. The issue is fundamental but fixable without changing the algorithmic intent. Let’s go step by step.
codeforces competitive-programming data-structures implementation Jun 11, 2026
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418F - Equal Product

Fix a value of $x1$. We need to find two different representations of the same product: $$x1 y1 = x2 y2,$$ with $x2 x1$, $y2 < y1$, and the product lying inside $[l,r]$. The output is required separately for every $x1$ from $1$ to $n$.
codeforces competitive-programming data-structures math number-theory two-pointers Jun 11, 2026
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418G - Three Occurrences

We are given an array of length $n$, and we want to count how many contiguous segments have the following property: every distinct value appearing inside that segment appears exactly three times. The condition is surprisingly restrictive.
codeforces competitive-programming data-structures divide-and-conquer hashing two-pointers Jun 11, 2026
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418E - Expected Damage

We have a fixed multiset of monster strengths. For each query, a shield starts with durability a and defence value b. Monsters are fought in a uniformly random order. A monster whose strength is at least b consumes one durability point but deals no damage.
codeforces competitive-programming binary-search combinatorics probabilities Jun 11, 2026
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418B - Negative Prefixes

We have an array and a second binary array describing which positions are locked and which are unlocked. A locked position must keep its original value. An unlocked position may receive any value that originally belonged to an unlocked position.
codeforces competitive-programming greedy sortings Jun 11, 2026
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418C - Mortal Kombat Tower

We are tasked with simulating a two-player cooperative challenge where bosses appear in a fixed order, and each boss is either easy or hard. The first player, your friend, cannot defeat hard bosses without consuming a skip point.
codeforces competitive-programming dp graphs greedy shortest-paths Jun 11, 2026
Practice › Codeforces Solutions › Educational Codeforces Round 95 (Rated for Div. 2) ›

CF 1418A - Buying Torches

We are asked to determine the minimum number of trades required to craft a given number of torches in a game. Each torch requires one stick and one coal. We start with a single stick.
codeforces competitive-programming math Jun 11, 2026