Codeforces Round 1087 (Div. 2)

6 problems from Codeforces Round 1087 (Div. 2) (contest 2209), difficulty 800-2700. 1/6 solutions verified against sample I/O.

6 items

Codeforces Round 1087 (Div. 2)

Div. 2 | 6 problems | 1/6 verified | Difficulty 800-2700 | 11m 5s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Flip Flops	800	greedy	21,430	2m 13s
B	Array	900	greedy	19,314	1m 27s	✓
C	Find the Zero	1400	constructive-algorithms, interactive	10,597	2m
D	Ghostfires	1800	constructive-algorithms, greedy	5,306	1m 47s
E	A Trivial String Problem	2200	brute-force, dp, hashing	1,755	1m 51s
F	Dynamic Values And Maximum Sum	2700	data-structures, greedy, implementation	412	1m 47s

Practice › Codeforces Solutions › Codeforces Round 1087 (Div. 2) ›

CF 2209F - Dynamic Values And Maximum Sum

We are given a tree of n vertices, where each vertex has an integer value. We can perform k operations, and in each operation, we choose a vertex to root the tree at. Once a vertex is chosen as the root, its value is added directly to the total and then set to zero.

Practice › Codeforces Solutions › Codeforces Round 1087 (Div. 2) ›

CF 2209E - A Trivial String Problem

We are given a string and a set of queries. For each query, we take a substring defined by its endpoints, and for every prefix of this substring, we compute the maximum number of pieces it can be split into such that each piece is itself a prefix of the substring.

Practice › Codeforces Solutions › Codeforces Round 1087 (Div. 2) ›

CF 2209D - Ghostfires

The problem asks us to construct a sequence of ghostfires in three colors: red, green, and blue. OtterZ has a limited number of each color, denoted by $r$, $g$, and $b$. The goal is to place as many ghostfires as possible in a row while avoiding two constraints.

Practice › Codeforces Solutions › Codeforces Round 1087 (Div. 2) ›

CF 2209A - Flip Flops

We are given a sequence of monsters, each with a strength value. We also start with an initial combat power. At any point, we can either defeat a monster if our current power is at least its strength, or we can spend a limited number of special items to increase a monster’s…

Practice › Codeforces Solutions › Codeforces Round 1087 (Div. 2) ›

CF 2209C - Find the Zero

We are asked to find a position of a zero in a hidden array of length $2n$, where each integer from $1$ to $n$ occurs exactly once and all remaining positions are zeros.

Practice › Codeforces Solutions › Codeforces Round 1087 (Div. 2) ›

CF 2209B - Array

We are given an array of integers, and for each element, we need to determine how many elements to its right can be “dominated” by it, in a specific sense.