Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2)
Solutions for Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2) (contest 2222). 0/6 problems verified against sample I/O. Difficulty range: -.
Spectral::Cup 2026 Round 1 (Codeforces Round 1094, Div. 1 + Div. 2)
Type: Div. 1+2 | Problems: 6 | Verified: 0/6 | Rating range: - | Time: 23m 39s
| Problem | Name | Rating | Tags | Solve Time | Verified |
|---|---|---|---|---|---|
| A | A Wonderful Contest | - | brute-force, dp, math | 4m 29s | ✗ |
| B | Artistic Balance Tree | - | greedy, sortings | 3m 53s | ✗ |
| C | Median Partition | - | dp, math | 2m 36s | ✗ |
| D | Permutation Construction | - | constructive-algorithms, data-structures, sortings | 4m 9s | ✗ |
| E | Seek the Truth | - | binary-search, bitmasks, constructive-algorithms | 1m 59s | ✗ |
| G | Statistics on Tree | - | binary-search, brute-force, dfs-and-similar | 6m 33s | ✗ |
CF 2222A - A Wonderful Contest
Each problem in the contest is worth at most 100 points. If a problem has $ai$ subtasks, then every solved subtask contributes $$frac{100}{ai}$$ points, and $ai$ is guaranteed to divide 100.
CF 2222B - Artistic Balance Tree
We have an array, and before each marking operation we are allowed to reverse any odd-length segment centered at some position. After that reversal, the element currently sitting at index xi becomes marked. The subtle detail is that marks belong to elements, not positions.
CF 2222C - Median Partition
The simulator maintains a global simulated time variable $CLOCK$ and executes each MIX instruction by dispatching to a routine that models its effect on registers, memory, and timing. The I/O instructions considered here are restricted to devices $16$ and $18$.
CF 2222D - Permutation Construction
We are given an array $a$ of length $n$. We must construct a permutation $p$ of indices $1$ to $n$. For any pair of positions $i<j$, the pair contributes to the score only if it is an inversion in $p$, meaning $pipj$.
CF 2222E - Seek the Truth
The original problem is interactive, but the version used for judging after the contest is the hacked format. Instead of interacting with a judge, each test case directly gives us the hidden values n, k, and c.
CF 2222G - Statistics on Tree
We are given a tree. For a pair of vertices $(u,v)$, we remove every edge belonging to the unique simple path between them. After those edges are deleted, the tree breaks into several connected components. The value of the pair is the size of the largest remaining component.