nb 莫比乌斯反演题，和常规套路不同。
BZOJ3811 玛里苟斯
Posted on
Symbols count in article: 2.4k Reading time ≈ 5 mins.
Symbols count in article: 2.4k Reading time ≈ 5 mins.
利用好了期望的性质，除了线性基几乎没有卡点，非常有意思。
CF Educational Round#125
Posted on
Symbols count in article: 5.8k Reading time ≈ 13 mins.
Symbols count in article: 5.8k Reading time ≈ 13 mins.
赛时偷瞄 F 难度，不小心看到了做法，结果还是不会……
AT Code Festival 2017 Qual B F Largest Smallest Cyclic Shift
Posted on
Symbols count in article: 2k Reading time ≈ 4 mins.
Symbols count in article: 2k Reading time ≈ 4 mins.
神秘贪心 + 构造题。
AT Code Festival 2017 Qual B E Popping Balls
Posted on
Symbols count in article: 1.1k Reading time ≈ 2 mins.
Symbols count in article: 1.1k Reading time ≈ 2 mins.
组合数学真有趣。
CF643F Bears and Juice
Posted on
Symbols count in article: 1.4k Reading time ≈ 3 mins.
Symbols count in article: 1.4k Reading time ≈ 3 mins.
有趣的信息量分析 + 组合数学题目。
LOJ2143 [SHOI2017]组合数问题
Posted on
Symbols count in article: 2.3k Reading time ≈ 5 mins.
Symbols count in article: 2.3k Reading time ≈ 5 mins.
有意思的一道题目，做法比较多。
LOJ2142 [SHOI2017]相逢是问候
Posted on
Symbols count in article: 2.5k Reading time ≈ 6 mins.
Symbols count in article: 2.5k Reading time ≈ 6 mins.
神秘扩展欧拉定理 + 均摊线段树。
LOJ2988 [CTSC2016]萨菲克斯 · 阿瑞
Posted on
Symbols count in article: 2.2k Reading time ≈ 5 mins.
Symbols count in article: 2.2k Reading time ≈ 5 mins.
奇怪的后缀数组计数。
CF Round#779
Posted on
Symbols count in article: 5.8k Reading time ≈ 13 mins.
Symbols count in article: 5.8k Reading time ≈ 13 mins.
LOJ2014 [SCOI2016]萌萌哒
Posted on
Symbols count in article: 1.2k Reading time ≈ 3 mins.
Symbols count in article: 1.2k Reading time ≈ 3 mins.
有趣的倍增 ST 表题目。
CF809E Surprise me!
Posted on
Symbols count in article: 4.7k Reading time ≈ 10 mins.
Symbols count in article: 4.7k Reading time ≈ 10 mins.
比较套路的莫比乌斯反演，以及虚树处理。
CF1109D Sasha and Interesting Fact from Graph Theory
Posted on
Symbols count in article: 1.1k Reading time ≈ 2 mins.
Symbols count in article: 1.1k Reading time ≈ 2 mins.
神秘 prufer 序列 + 组合数学。
Luogu P5219 无聊的水题 I
Posted on
Symbols count in article: 806 Reading time ≈ 2 mins.
Symbols count in article: 806 Reading time ≈ 2 mins.
prufer 序列 + 多项式重工业。
LOJ2106 [JLOI2015]有意义的字符串
Posted on
Symbols count in article: 1.2k Reading time ≈ 3 mins.
Symbols count in article: 1.2k Reading time ≈ 3 mins.
经典矩阵乘法计算无理数幂题目。
LOJ2320 「清华集训 2017」生成树计数
Posted on
Symbols count in article: 2.1k Reading time ≈ 5 mins.
Symbols count in article: 2.1k Reading time ≈ 5 mins.
有难度的树上计数 + 多项式重工业。
AT Code Festival 2017 Qual A F Squeezing Slimes
Posted on
Symbols count in article: 743 Reading time ≈ 2 mins.
Symbols count in article: 743 Reading time ≈ 2 mins.
有趣的结论题。
AGC038E Gachapon
Posted on
Symbols count in article: 880 Reading time ≈ 2 mins.
Symbols count in article: 880 Reading time ≈ 2 mins.
DP 优化 min-max 容斥套路似乎是 min-max 容斥唯一考法了……
Luogu P5850 calc加强版
Posted on
Symbols count in article: 1.4k Reading time ≈ 3 mins.
Symbols count in article: 1.4k Reading time ≈ 3 mins.
又是多项式重工业。
CF Round Global#21
Posted on
Symbols count in article: 4.1k Reading time ≈ 9 mins.
Symbols count in article: 4.1k Reading time ≈ 9 mins.