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Top Rated Accepted
#294: Forever_Young
Accepted: : 271
#294: KevinLikesCoding
Accepted: : 271
$$\pi(n)=\phi\left(n,\pi\left(n^\frac{1}{3}\right)\right)-\pi\left (n^\frac{1}{3} \right ) + 1 - \sum_{p\in \left(n^\frac{1}{3},n^\frac{1}{2} \right] } \pi \left (\frac{n}{p} \right )-\pi(p)+1 $$
#296: CSQ
Accepted: : 270
#296: KobicGend
Accepted: : 270
#298: AFewSuns
Accepted: : 269
$\displaystyle\sum_{n \geq 0}{(x+y)^n\frac{u^n}{n!}}=\sum_{k \geq 0}\frac{x}{x-kz}(x-kz)^k\frac{u^k}{k!}\sum_{l \geq 0}\frac{(y+kz)^l}{l!}u^l$
#299: ucup-team122
Accepted: : 265
#300: ucup-team110
Accepted: : 262
#301: garam1732
Accepted: : 260
#302: hydd
Accepted: : 259
But are we all lost stars trying to light up the dark?
#302: ucup-team1447
Accepted: : 259
没队要
#302: wcyQwQ
Accepted: : 259
#305: He_Ren
Accepted: : 258
#306: SirTechnical
Accepted: : 257
#306: ucup-team4527
Accepted: : 257
#306: ucup-team5071
Accepted: : 257
#309: sleep
Accepted: : 256
#309: yangjiaxi
Accepted: : 256
#311: huaxiamengjin
Accepted: : 254
#311: XY_Eleven
Accepted: : 254
#311: zhenjianuo2025
Accepted: : 254
#314: ushg8877
Accepted: : 253
#315: Seniorious
Accepted: : 252
We do not know and will not know
#315: tzl_Dedicatus545
Accepted: : 252
忙碌着 无为着 继续
#317: elacient
Accepted: : 251
#317: hshhh
Accepted: : 251
#317: nanika
Accepted: : 251
#317: ucup-team3515
Accepted: : 251
#321: IllusionaryDominance
Accepted: : 249
#322: jiamengtong
Accepted: : 248
#322: travel
Accepted: : 248
#322: ucup-team180
Accepted: : 248
#325: tricyzhkx
Accepted: : 247
#325: ucup-team2307
Accepted: : 247
#327: ucup-team2172
Accepted: : 246
法克皮百吨
#328: 617lyq
Accepted: : 245
#328: liuziao
Accepted: : 245
#328: ucup-team1293
Accepted: : 245
#328: xDarkbluex
Accepted: : 245
#332: jqh333
Accepted: : 244
#333: jrjyy
Accepted: : 243
#333: Register
Accepted: : 243
#333: ucup-team2045
Accepted: : 243
#333: Zero_OP
Accepted: : 243
#337: DinoHadzic
Accepted: : 242
#337: luanyanjia
Accepted: : 242
#337: lunchbox
Accepted: : 242
#340: std
Accepted: : 241
哼
#341: Diaosi
Accepted: : 240
#341: nathan4690
Accepted: : 240
#343: carrotqq
Accepted: : 239
#343: ucup-team267
Accepted: : 239
哈姆。
#345: Sktn0089
Accepted: : 236
#345: ucup-team135
Accepted: : 236
#347: as_lyr
Accepted: : 235
#347: iee
Accepted: : 235
#347: MarSer020
Accepted: : 235
#350: ETK
Accepted: : 234
「我是星 我愿投身前途未卜的群星，为梦长明。」
#350: Journey_to_Edge_Ring
Accepted: : 234
ECUST_飞向边界环 (est. 2025)Member:hatertumu1thuguanfu
#350: RDFZchenyy
Accepted: : 234
悟已往之不谏，知来者之可追。实迷途其未远，觉今是而昨非。
#350: wsxcb
Accepted: : 234
#354: 2021cyq
Accepted: : 233
#354: ucup-team6749
Accepted: : 233
#356: moriko
Accepted: : 232
#356: ucup-team4269
Accepted: : 232
#356: ucup-team7725
Accepted: : 232
#359: MatrixGroup
Accepted: : 231
どうか どうか どうか | 可是真实的人生，必定是单调、残酷，而缺乏色彩的
#359: ucup-team3586
Accepted: : 231
#359: ucup-team5984
Accepted: : 231
#359: ucup-team6748
Accepted: : 231
#359: ucup-team7832
Accepted: : 231
#364: ucup-team5008
Accepted: : 230
#364: ucup-team7754
Accepted: : 230
#366: ucup-team7466
Accepted: : 229
#367: Calculatelove
Accepted: : 228
Love all my perfect imperfections.
#367: qzez
Accepted: : 228
对于无向图的情况，基尔霍夫矩阵为 $K=D-A$，其中 $D$ 为度数矩阵，$A$ 为邻接矩阵。树的个数为去掉 $K$ 一行一列的行列式的值。对于外向树，$D$ 为每个点的入边度数和，内向树相反。此时需要去掉根所在行列。BEST 定理：有向欧拉图的欧拉回路个数为：内向树个数乘以 $\prod\limits_{i=1}^{n}deg_i$，其中 $deg_i$ 为 $i$ 号点的度数。
#369: cmll02
Accepted: : 227
#369: sunnygreen
Accepted: : 227
https://www.luogu.com.cn/article/1w0l0mmq
#369: ucup-team7683
Accepted: : 227
一直游到海水变蓝
#372: chenshi
Accepted: : 226
#373: feecle6418
Accepted: : 225
gyh ak ioi
#374: bamboo123
Accepted: : 224
#374: lnw143
Accepted: : 224
what doesn't kill you makes you stronger
#374: SoyTony
Accepted: : 224
真実はいつもひとつ
#374: ucup-team4464
Accepted: : 224
#378: 8BQube
Accepted: : 223
#378: ucup-team2819
Accepted: : 223
#378: zdczdc
Accepted: : 223
#381: Prime
Accepted: : 222
#382: intiger
Accepted: : 221
#383: ETO_leader
Accepted: : 220
#383: xmdxmdxmd
Accepted: : 220
#385: binminh01
Accepted: : 219
#385: ChiFAN
Accepted: : 219
你是翅膀也是我肩膀
#385: masterhuang
Accepted: : 219
不要逃避自己的命运
#385: ucup-team4478
Accepted: : 219
#385: xlwang
Accepted: : 219
#390: alex9801
Accepted: : 217
#390: Arkweedy
Accepted: : 217
#390: Crosselle
Accepted: : 217
#390: houzhiyuan
Accepted: : 217