Codeforces Round 1039 (Div. 2)

Solutions for Codeforces Round 1039 (Div. 2) (contest 2128). 2/7 problems verified against sample I/O. Difficulty range: 800-3200.

7 items

Codeforces Round 1039 (Div. 2)

Type: Div. 2 | Problems: 7 | Verified: 2/7 | Rating range: 800-3200 | Time: 14m 46s

Problem Name Rating Tags Solve Time Verified
A Recycling Center 800 greedy, sortings 1m 12s ✓
B Deque Process 1100 constructive-algorithms, greedy, sortings 1m 39s ✗
C Leftmost Below 1200 greedy, math 2m 16s ✓
D Sum of LDS 1600 brute-force, combinatorics, dp 3m 7s ✗
E1 Submedians (Easy Version) 1900 binary-search, data-structures, dp 1m 36s ✗
E2 Submedians (Hard Version) 2600 binary-search, constructive-algorithms, data-structures 1m 50s ✗
F Strict Triangle 3200 graphs, greedy, shortest-paths 3m 6s ✗
Practice › Codeforces Solutions › Codeforces Round 1039 (Div. 2) ›

CF 2128F - Strict Triangle

We are given an undirected, connected graph with $n$ nodes and $m$ edges, where each edge has a weight that is not fixed but lies in a given interval $[li, ri]$.
codeforces competitive-programming graphs greedy shortest-paths Jun 8, 2026
Practice › Codeforces Solutions › Codeforces Round 1039 (Div. 2) ›

CF 2128E2 - Submedians (Hard Version)

We are asked to identify submedians in an array. More concretely, for each integer in the array range $1$ to $n$, we want to determine whether there exists a contiguous subarray of length at least $k$ such that the integer is a median of that subarray.
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CF 2128D - Sum of LDS

The failure you’re seeing is not an algorithmic issue at all. It’s a complete breakdown of input handling consistency across the solution.
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Practice › Codeforces Solutions › Codeforces Round 1039 (Div. 2) ›

CF 2128B - Deque Process

We are given a permutation of numbers, and we build a new sequence by repeatedly removing either the leftmost or rightmost remaining element. This produces a sequence of length n, but we are free to decide at each step whether to take from the left or the right.
codeforces competitive-programming constructive-algorithms greedy sortings two-pointers Jun 8, 2026
Practice › Codeforces Solutions › Codeforces Round 1039 (Div. 2) ›

CF 2128E1 - Submedians (Easy Version)

We are given an array and a length constraint $k$. From this array, we want to select a contiguous segment of length at least $k$.
codeforces competitive-programming binary-search data-structures dp greedy math Jun 8, 2026
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CF 2128C - Leftmost Below

We start with an array of length n, filled with zeros. An operation chooses a positive integer x that is strictly larger than the current minimum value in the array. The operation does not let us choose which position receives the increment.
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Practice › Codeforces Solutions › Codeforces Round 1039 (Div. 2) ›

CF 2128A - Recycling Center

We are given several independent scenarios. In each scenario there is a collection of bags, each with an initial weight. Time proceeds in discrete seconds. At every second we are forced to remove exactly one remaining bag.
codeforces competitive-programming greedy sortings Jun 8, 2026