Codeforces Round 980 (Div. 1)

Solutions for Codeforces Round 980 (Div. 1) (contest 2023). 1/6 problems verified against sample I/O. Difficulty range: 1300-3500.

6 items

Codeforces Round 980 (Div. 1)

Type: Div. 1 | Problems: 6 | Verified: 1/6 | Rating range: 1300-3500 | Time: 11m 30s

Problem Name Rating Tags Solve Time Verified
A Concatenation of Arrays 1300 constructive-algorithms, greedy, math 2m 16s ✗
B Skipping 1700 binary-search, dp, graphs 2m 23s ✗
C C+K+S 2400 constructive-algorithms, dfs-and-similar, graphs 1m 49s ✗
D Many Games 2900 brute-force, dp, greedy 1m 47s ✓
E Tree of Life 3300 dp, greedy, trees 1m 40s ✗
F Hills and Pits 3500 data-structures, greedy, math 1m 35s ✗
Practice › Codeforces Solutions › Codeforces Round 980 (Div. 1) ›

CF 2023F - Hills and Pits

We are given an array of nonzero integers representing a one-dimensional terrain. Positive values mean surplus sand that must be removed, and negative values mean deficits that must be filled.
codeforces competitive-programming data-structures greedy math matrices Jun 8, 2026
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CF 2023E - Tree of Life

We are given a tree of n nodes, which are connected by n-1 edges. Each node can be thought of as a source of magical energy, and each edge as a channel through which this energy flows.
codeforces competitive-programming dp greedy trees Jun 8, 2026
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CF 2023D - Many Games

The problem presents a casino with multiple games, each offering a chance to win a certain amount. Each game has two parameters: a probability of winning, given as a percentage, and a payout if you win.
codeforces competitive-programming brute-force dp greedy math probabilities Jun 8, 2026
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CF 2023B - Skipping

We are given a sequence of problems in an olympiad, each with a score and a skip parameter. The competition begins with the first problem.
codeforces competitive-programming binary-search dp graphs shortest-paths Jun 8, 2026
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CF 2023A - Concatenation of Arrays

We are given n arrays, and every array contains exactly two numbers. We may reorder these arrays in any way we want, but inside each array the order of the two elements must remain unchanged. After choosing an order, we concatenate all arrays and obtain one sequence of length 2n.
codeforces competitive-programming constructive-algorithms greedy math sortings Jun 8, 2026
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CF 2023C - C+K+S

We are given two directed graphs, each with the same number of vertices. Each graph is already strongly connected, and every directed cycle inside each graph has length divisible by a fixed integer $k$.
codeforces competitive-programming constructive-algorithms dfs-and-similar graphs greedy hashing implementation strings Jun 8, 2026