Codeforces Round 1007 (Div. 2)

7 problems from Codeforces Round 1007 (Div. 2) (contest 2071), difficulty 800-2700. 1/7 solutions verified against sample I/O.

7 items

Codeforces Round 1007 (Div. 2)

Div. 2 | 7 problems | 1/7 verified | Difficulty 800-2700 | 11m 44s

# Problem Rating Tags Accepted Time ✓
A The Play Never Ends 800 math, number-theory 27,839 1m 13s ✓
B Perfecto 1100 brute-force, constructive-algorithms, greedy 20,877 1m 40s
C Trapmigiano Reggiano 1700 constructive-algorithms, data-structures, dfs-and-similar 9,693 2m 14s
D1 Infinite Sequence (Easy Version) 1800 bitmasks, brute-force, dp 6,692 1m 43s
D2 Infinite Sequence (Hard Version) 2500 bitmasks, brute-force, constructive-algorithms 1,100 2m 4s
E LeaFall 2600 combinatorics, dp, probabilities 819 1m 31s
F Towering Arrays 2700 binary-search, data-structures 332 1m 19s
Practice › Codeforces Solutions › Codeforces Round 1007 (Div. 2) ›

CF 2071F - Towering Arrays

We are given an array of integers and the ability to remove up to k elements. The goal is to maximize an integer p such that the remaining array can be structured as a p-towering array.
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CF 2071D2 - Infinite Sequence (Hard Version)

We are given a binary sequence where the first $n$ values are fixed as input. After that, the sequence continues infinitely, but it is no longer explicitly stored.
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CF 2071E - LeaFall

We are given a tree with n vertices, where each vertex i has a probability pi/qi of "falling". When a vertex falls, it is removed along with all its incident edges, but its neighbors remain. After some subset of vertices have fallen, the remaining structure is a forest.
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CF 2071D1 - Infinite Sequence (Easy Version)

We are given the first $n$ elements of an infinite binary sequence, where each element after the $n$-th is defined recursively as the XOR of all previous elements up to half its index.
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CF 2071C - Trapmigiano Reggiano

We are given a tree, a starting vertex st, and a target vertex en. A permutation of all vertices must be chosen. During the i-th step, a piece of cheese appears at vertex p[i]. If the mouse is already there, it stays.
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CF 2071B - Perfecto

We are asked to construct a permutation of numbers from 1 to n such that no prefix sum of the permutation is a perfect square. The input provides several test cases, each specifying an integer n.
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CF 2071A - The Play Never Ends

Three players repeatedly play matches where exactly two are active and one is watching. The role assignment evolves deterministically from the previous match using two rules. If someone has already played two matches in a row, they are forced to sit out next.
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