2021 ICPC Southeastern Europe Regional Contest

14 problems from 2021 ICPC Southeastern Europe Regional Contest (contest 103438), difficulty -. 13/14 solutions verified against sample I/O.

14 items

2021 ICPC Southeastern Europe Regional Contest

ICPC/IOI | 14 problems | 13/14 verified | Difficulty - | 13m 9s

#	Problem	Time	✓
A	King of String Comparison	53s	✓
B	New Queries On Segment Deluxe	1m 33s	✓
C	Werewolves	1m 6s	✓
D	Many LCS	53s	✓
E	Replace Sort	1m	✓
F	to Pay Respects	46s	✓
G	Max Pair Matching	1m 3s	✓
H	Colourful Permutation Sorting	50s	✓
I	Flood Fill	59s	✓
J	ABC Legacy	53s	✓
K	Amazing Tree	48s	✓
L	Jason ABC	41s
M	Counting Phenomenal Arrays	47s	✓
N	A-series	57s	✓

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438N - A-series

We are given a hierarchy of paper sizes from $A0$ down to $AN$, where each level is exactly half the size of the previous one. You start with some initial inventory of sheets at each size, and you also have a target inventory you want to achieve.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438M - Counting Phenomenal Arrays

We are asked to count special arrays of positive integers where multiplication and addition give the same result. For an array of length $k$, if the product of all elements equals the sum of all elements, we call it valid.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438L - Jason ABC

Working

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438F - to Pay Respects

The game runs for a fixed number of rounds, and in each round the boss and the player interact through a shared system of stacking effects.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438K - Amazing Tree

We are given a tree, and we are allowed to run a depth-first search that produces a post-order sequence: a node is written to the output only after all of its unvisited neighbors have been recursively processed. The twist is that we are not constrained to a fixed DFS behavior.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438J - ABC Legacy

We are given a string of length $2n$, consisting only of the letters A, B, and C. The task is to split the set of positions of this string into $n$ disjoint pairs.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438I - Flood Fill

We are given two binary grids of the same size. Each cell is either 0 or 1, representing white or black. We start from grid A and are allowed to apply an operation that picks any cell, takes the entire connected region of equal-valued cells containing it, and flips every value…

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438H - Colourful Permutation Sorting

We are given a permutation of size $n$, but the positions of this permutation are grouped by colors. We are allowed to fix the permutation using two kinds of actions: we can swap any two elements paying a fixed cost $S$, and we can also pick a color class and arbitrarily…

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438G - Max Pair Matching

We are given a collection of 2n objects, each object i described by two integers ai and bi. You can think of each object as a segment on the number line, although the endpoints are not guaranteed to be ordered.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438E - Replace Sort

We are given an array that we are not allowed to reorder and a second set of spare numbers that can be used as replacements.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438D - Many LCS

We are asked to construct two binary strings, call them S and T, with lengths up to a fixed limit. The goal is not to optimize a standard objective like LCS length itself, but to control the structure of the set of all longest common subsequences.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438A - King of String Comparison

We are given two strings of equal length, say s and t, both indexed from 1 to n. For every substring that starts at position l and ends at position r, we compare the substring s[l..r] with t[l..r] using standard lexicographic ordering.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438B - New Queries On Segment Deluxe

We are given a matrix with at most four rows and up to a quarter million columns. From each column we derive a single value by summing all rows in that column. So every version of the matrix corresponds to a one-dimensional array derived from column-wise sums.

Practice › Codeforces Solutions › 2021 ICPC Southeastern Europe Regional Contest ›

CF 103438C - Werewolves

We are working with a tree where each node has a color label. The task is to look at every connected set of nodes inside this tree, meaning any subset of vertices whose induced subgraph stays connected, and decide whether that set has a “majority color”.