Codeforces Round 1052 (Div. 2)

7 problems from Codeforces Round 1052 (Div. 2) (contest 2146), difficulty 800-2900. 2/7 solutions verified against sample I/O.

7 items

Codeforces Round 1052 (Div. 2)

Div. 2 | 7 problems | 2/7 verified | Difficulty 800-2900 | 11m 46s

# Problem Rating Tags Accepted Time ✓
A Equal Occurrences 800 brute-force, greedy, implementation 21,830 1m 12s ✓
B Merging the Sets 1100 greedy, implementation 15,915 1m 40s ✓
C Wrong Binary Search 1300 binary-search, constructive-algorithms 13,304 1m 32s
D1 Max Sum OR (Easy Version) 1500 bitmasks, constructive-algorithms, divide-and-conquer 10,450 1m 34s
D2 Max Sum OR (Hard Version) 2000 bitmasks, constructive-algorithms, divide-and-conquer 4,033 1m 36s
E Yet Another MEX Problem 2300 brute-force, constructive-algorithms, data-structures 2,053 1m 47s
F Bubble Sort 2900 brute-force, combinatorics, dp 302 2m 25s
Practice › Codeforces Solutions › Codeforces Round 1052 (Div. 2) ›

CF 2146F - Bubble Sort

The task is to count permutations of length $n$ that satisfy a specific condition derived from bubble sort. For a permutation $p$, define $bi$ as the number of bubble sort rounds required to sort the prefix $[p1, dots, pi]$.
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CF 2146E - Yet Another MEX Problem

We are given an array that grows one element at a time from left to right. After each new element is appended, we look at all subarrays that end exactly at this new position. Among those subarrays, we want the one that maximizes a particular score.
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CF 2146D2 - Max Sum OR (Hard Version)

We are given an integer interval $[l, r]$. From this interval we form a list containing every integer exactly once. One copy of this list is fixed as array $b$. The other copy, array $a$, is initially identical but we are allowed to permute it arbitrarily.
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CF 2146D1 - Max Sum OR (Easy Version)

We are given two integers, l and r, where l is always zero in this easy version and r is less than 200,000. From these, we define an array b that contains every integer from l to r, inclusive. We are allowed to permute a copy of this array, which we call a.
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CF 2146B - Merging the Sets

We are given several collections of integers, where each collection can be thought of as a “bundle of labels” from the range $1$ to $m$.
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CF 2146C - Wrong Binary Search

We are asked to construct a permutation of integers from 1 to n based on a binary string that marks which numbers are “stable” under a randomized variant of binary search.
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CF 2146A - Equal Occurrences

We are given a non-decreasing array of integers, and we want to find a subsequence whose elements all appear the same number of times. A subsequence can skip elements but cannot change their order.
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