Educational Codeforces Round 91 (Rated for Div. 2)

5 problems from Educational Codeforces Round 91 (Rated for Div. 2) (contest 1380), difficulty 1400-2600. 3/5 solutions verified against sample I/O.

5 items

Educational Codeforces Round 91 (Rated for Div. 2)

Div. 2 | 5 problems | 3/5 verified | Difficulty 1400-2600 | 22m 23s

#	Problem	Rating	Tags	Accepted	Time	✓
B	Universal Solution	1400	greedy	15,281	5m 4s
C	Create The Teams	1400	brute-force, dp, greedy	22,708	1m 31s	✓
E	Merging Towers	2300	data-structures, dsu, implementation	2,409	7m 10s	✓
F	Strange Addition	2600	data-structures, dp, matrices	891	2m 24s
G	Circular Dungeon	2600	greedy, math, probabilities	935	6m 14s	✓

Practice › Codeforces Solutions › Educational Codeforces Round 91 (Rated for Div. 2) ›

CF 1380G - Circular Dungeon

We are placing a multiset of values into a circular array of rooms. Each room contains exactly one item, and each item is either a regular chest with a reward value or a mimic that immediately stops the run when entered.

Practice › Codeforces Solutions › Educational Codeforces Round 91 (Rated for Div. 2) ›

CF 1380E - Merging Towers

We are given a set of numbered discs from 1 to n, where larger numbers represent larger discs. These discs are initially split across m towers, and each tower already has its discs stacked in decreasing order of size from bottom to top.

Practice › Codeforces Solutions › Educational Codeforces Round 91 (Rated for Div. 2) ›

CF 1380B - Universal Solution

We are given a string describing a cyclic opponent strategy in a rock-paper-scissors game. The opponent does not adapt; instead, they choose moves according to a fixed circular string. If they start at some position, they follow the string in order and wrap around forever.

Practice › Codeforces Solutions › Educational Codeforces Round 91 (Rated for Div. 2) ›

CF 1380F - Strange Addition

The revised submission correctly identifies the structure of the problem: it must first maximize the number of leading digits equal to $d$, then select the largest 50-digit prime with that prefix.

Practice › Codeforces Solutions › Educational Codeforces Round 91 (Rated for Div. 2) ›

CF 1380C - Create The Teams

We have a group of programmers, each with a skill value. We want to form as many teams as possible. A team is valid if: $$(text{team size}) times (text{minimum skill in the team}) ge x$$ Every programmer can belong to at most one team, and some programmers may remain unused.