Codeforces Round 1053 (Div. 1)

8 problems from Codeforces Round 1053 (Div. 1) (contest 2150), difficulty 1300-3500. 0/8 solutions verified against sample I/O.

8 items

Codeforces Round 1053 (Div. 1)

Div. 1 | 8 problems | 0/8 verified | Difficulty 1300-3500 | 15m 14s

# Problem Rating Tags Accepted Time ✓
A Incremental Path 1300 data-structures, hashing, implementation 11,684 1m 41s
B Grid Counting 1700 combinatorics, implementation, math 6,046 2m 32s
C Limited Edition Shop 2100 data-structures, dp 2,653 1m 41s
D Attraction Theory 2700 combinatorics, dp, math 752 1m 42s
E1 Hidden Single (Version 1) 2600 divide-and-conquer, interactive, math 1,026 1m 42s
E2 Hidden Single (Version 2) 2800 binary-search, divide-and-conquer, interactive 598 1m 45s
F Cycle Closing 3000 constructive-algorithms, graphs, implementation 203 1m 50s
G Counting Is Fun: The Finale 3500 combinatorics, implementation 82 2m 21s
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CF 2150G - Counting Is Fun: The Finale

We are asked to count how many binary strings of fixed length and fixed composition can be formed such that two conditions hold simultaneously: the string must dominate a given reference string in lexicographic order, and it must admit at least one split point where both…
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CF 2150F - Cycle Closing

We are given a connected simple undirected graph. The graph is already partially filled with edges, and our goal is to make it a complete graph, meaning every pair of distinct vertices must end up connected by an edge. We are not allowed to directly add edges.
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CF 2150E2 - Hidden Single (Version 2)

We are given a hidden array of length $2n-1$ that contains each number from 1 to $n$ exactly twice, except for a single number which appears only once. Our goal is to determine which number appears only once. We do not need to know its position, only its identity.
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CF 2150E1 - Hidden Single (Version 1)

We are given a hidden array of length 2n-1, containing integers from 1 to n such that every number appears exactly twice except for one number that appears only once. Our goal is to identify the number that occurs exactly once. We do not need its position, only its value.
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CF 2150D - Attraction Theory

We start with n people placed on positions 1 through n on a line. The initial configuration is completely rigid: person i starts at position i.
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CF 2150B - Grid Counting

We are asked to count the number of ways to color cells black in an $n times n$ grid given a list $a$ of length $n$. The entry $ak$ specifies how many black cells must appear in row $k$.
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CF 2150A - Incremental Path

We are given a line of $10^9$ cells, each either black or white. Initially, a certain set of cells are black, and all others are white.
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CF 2150C - Limited Edition Shop

We are asked to analyze a situation where two players, Alice and Bob, pick objects from a shop in turn. Each object has a value from our perspective, and each player has their own preference order.
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