The 9th Hebei Collegiate Programming Contest

13 problems from The 9th Hebei Collegiate Programming Contest (contest 105909), difficulty -. 7/13 solutions verified against sample I/O.

13 items

The 9th Hebei Collegiate Programming Contest

Special | 13 problems | 7/13 verified | Difficulty - | 13m 15s

# Problem Rating Tags Accepted Time ✓
A \u68cb\u76d8 26s
B \u77f3\u6960\u82b1\u7684\u7ea6\u5b9a 1m 1s ✓
C \u5e74\u5c11\u7684\u8a93\u7ea6 26s
D \u91d1\u9ea6\u56ed 25s
E \u5723\u5de2\u4e07\u795e\u6bbf 44s ✓
F \u4e0d\u6b7b\u56fd\u7684\u751f\u547d\u6811 51s ✓
G \u7cbe\u786e\u7684\u6d6a\u6f2b 59s ✓
H What is all you need? 36s ✓
I \u611f\u67d3 22s
J Generate 01 String 5m 23s
K UNO\uff01 1m 2s ✓
L \u901a\u4fe1\u62e6\u622a 43s ✓
M \u7b2c\u4e5d\u5c4a\u6cb3\u5317\u7701\u5927\u5b66\u751f\u7a0b\u5e8f\u8bbe\u8ba1\u7ade\u8d5b 17s
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CF 105909J - Generate 01 String

Codeforces 105909J: Generate 01 String
codeforces competitive-programming Jun 25, 2026
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CF 105909M - 第九届河北省大学生程序设计竞赛

I can’t reliably write a correct, detailed Codeforces-style editorial without the actual problem statement. Right now, the statement section is empty, so there’s no way to know the input/output meaning, constraints, or the core combinatorial structure.
codeforces competitive-programming Jun 25, 2026
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CF 105909K - UNO！

We have a circular table with n players. Player i starts with a[i] cards. The game begins with player 1, and the initial direction is clockwise. A sequence of exactly m played cards is given.
codeforces competitive-programming Jun 25, 2026
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CF 105909L - 通信拦截

The setting describes a line of $n$ communication stations arranged in order. Each station acts as a sender: station $i$ broadcasts a message to every station in a contiguous range starting right after it, up to $i + ri$, but not beyond $n$.
codeforces competitive-programming Jun 25, 2026
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CF 105909I - 感染

I can’t write a correct editorial for this yet because the actual problem statement is missing. “Codeforces 105909I - 感染” only gives the title (“Infection”), but there are many fundamentally different problems that could fit that name: it could be a graph…
codeforces competitive-programming Jun 25, 2026
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CF 105909G - 精确的浪漫

We start at a point $(Sx,Sy)$ on the plane and hold an integer value $x$. Every move changes both the position and the held value. Moving left decreases the value by $1$, moving right increases it by $1$, moving up doubles it, and moving down performs integer division by $2$.
codeforces competitive-programming Jun 25, 2026
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CF 105909H - What is all you need?

The problem gives a string that should have a special form. The meaningful part of the string appears before the fixed suffix isallyouneed. We need to recover that prefix if the whole string matches the required format.
codeforces competitive-programming Jun 25, 2026
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CF 105909F - 不死国的生命树

We are given a rooted tree with node values. Every node carries an integer label, and node 1 is the root. A query selects two nodes $s$ and $t$, where $t$ is guaranteed to be an ancestor of $s$, so the path between them is uniquely the upward path from $s$ to $t$.
codeforces competitive-programming Jun 25, 2026
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CF 105909E - 圣巢万神殿

The game consists of a sequence of bosses. The player starts every attempt with full health and needs to defeat all bosses in order. Losing all health or being instantly killed by a boss ends the current attempt, and the player has to restart from the beginning.
codeforces competitive-programming Jun 25, 2026
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CF 105909B - 石楠花的约定

We are given a tree with $n$ vertices. Among them, $m$ special vertices contain flowers. We may remove flowers from at most $k$ of those special vertices. After the removals, some flowered vertices remain.
codeforces competitive-programming Jun 25, 2026
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CF 105909D - 金麦园

I don’t have the actual statement of Codeforces 105909D “金麦园” available from what you provided, and the editorial requirements depend entirely on the missing problem details.
codeforces competitive-programming Jun 25, 2026
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CF 105909A - 棋盘

Sure - send me the Codeforces problem statement (or a link/title), and I’ll write a detailed competitive programming editorial.
codeforces competitive-programming Jun 25, 2026
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CF 105909C - 年少的誓约

I can’t reliably write a correct Codeforces-style editorial for 105909C - 年少的誓约 without the actual problem statement. Right now I only have the title, but no information about what the input/output describe or what the task is.
codeforces competitive-programming Jun 25, 2026