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E. Wooden Game You are given a forest of $k$ rooted trees$^{\text{∗}}$. Lumberjack Timofey wants to cut down the entire forest by applying the followi 阅读全文
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parent 树上启发式合并 题目描述 $LH$ 拿到了一个字符串 $S$，他想要和你玩个游戏，每次 $LH$ 询问你一个字符串 $T$，和一个整数 $k$，你需要回答，字符串 $T$ 在 $S$ 中从左到右出现第 $k$ 次的位置在哪。 假如 $S[l \sim r]=T$，那么字符串 $T$ 在 阅读全文
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D. The Omnipotent Monster Killer You, the monster killer, want to kill a group of monsters. The monsters are on a tree with $n$ vertices. On vertex wi 阅读全文
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G2. Permutation Problem (Hard Version) This is the hard version of the problem. The only difference is that in this version $n \leq 5 \cdot 10^5$ and 阅读全文
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G - AtCoder Tour Problem Statement AtCoder Land is represented by a grid with $H$ rows and $W$ columns. Let $(i, j)$ denote the cell at the $i$-th row 阅读全文
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C2. Magnitude (Hard Version) The two versions of the problem are different. You may want to read both versions. You can make hacks only if both versio 阅读全文
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F - Two Sequence Queries Problem Statement You are given sequences of length $N$, $A=(A_1,A_2,\ldots,A_N)$ and $B=(B_1,B_2,\ldots,B_N)$.You are also g 阅读全文
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G. Yasya and the Mysterious Tree Yasya was walking in the forest and accidentally found a tree with $n$ vertices. A tree is a connected undirected gra 阅读全文
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D. Invertible Bracket Sequences A regular bracket sequence is a bracket sequence that can be transformed into a correct arithmetic expression by inser 阅读全文
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D. XORificator You are given a binary (consisting only of 0s and 1s) $n \times m$ matrix. You are also given a XORificator, using which you can invert 阅读全文