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Top Rated Accepted
#494: MarSer020
Accepted: : 235
#494: ucup-team135
Accepted: : 235
#494: ucup-team8618
Accepted: : 235
#494: zr
Accepted: : 235
#498: ETK
Accepted: : 234
「我是星 我愿投身前途未卜的群星，为梦长明。」
#498: ucup-team8683
Accepted: : 234
#498: wsxcb
Accepted: : 234
#498: xmdxmdxmd
Accepted: : 234
#502: cbant15
Accepted: : 233
#502: ucup-team6977
Accepted: : 233
#504: lsj2009
Accepted: : 232
#504: Prime
Accepted: : 232
#504: ucup-team4269
Accepted: : 232
#504: ucup-team6634
Accepted: : 232
#504: zhenghanyun
Accepted: : 232
#509: 2021cyq
Accepted: : 231
#509: moriko
Accepted: : 231
#509: Nanako7_ix
Accepted: : 231
#509: ucup-team6748
Accepted: : 231
#513: rainygame
Accepted: : 230
#513: ucup-team3586
Accepted: : 230
#513: ucup-team5008
Accepted: : 230
#513: ucup-team7697
Accepted: : 230
#517: MatrixGroup
Accepted: : 229
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
#517: ucup-team5984
Accepted: : 229
#519: Calculatelove
Accepted: : 228
Love all my perfect imperfections.
#519: gmroh
Accepted: : 228
#519: kjhhjki
Accepted: : 228
#519: 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。
#519: TheBlackFire
Accepted: : 228
#519: vlomaczk
Accepted: : 228
#519: Wansur
Accepted: : 228
#519: ZnPdCo
Accepted: : 228
#527: cmll02
Accepted: : 227
#527: do_while_true
Accepted: : 227
#527: KnownError_
Accepted: : 227
#527: ucup-team2262
Accepted: : 227
#531: feecle6418
Accepted: : 226
gyh ak ioi
#532: andreyDagger
Accepted: : 225
#532: asdfsdf
Accepted: : 225
#532: chenshi
Accepted: : 225
#532: monirr
Accepted: : 225
#532: zzzYheng
Accepted: : 225
你好我的朋友
#537: Lenisel
Accepted: : 224
#537: ucup-team7532
Accepted: : 224
#537: ucup-team7678
Accepted: : 224
#540: 8BQube
Accepted: : 223
#540: Thuw
Accepted: : 223
#540: ucup-team2819
Accepted: : 223
#543: msk_sama
Accepted: : 222
#543: SoyTony
Accepted: : 222
真実はいつもひとつ
#543: ucup-team7411
Accepted: : 222
#543: ucup-team968
Accepted: : 222
#547: treks
Accepted: : 221
#548: Arkweedy
Accepted: : 220
#548: Survivor_winner
Accepted: : 220
$$|\mathcal F^\downarrow||\mathcal G^\uparrow|\ge 2^n|\mathcal F^\downarrow\cap \mathcal G^\uparrow|$$
#548: xlwang
Accepted: : 220
#551: houzhiyuan
Accepted: : 219
#551: masterhuang
Accepted: : 219
不要逃避自己的命运
#551: tttfred
Accepted: : 219
#551: ucup-team4478
Accepted: : 219
#551: ucup-team8660
Accepted: : 219
#556: rui_er
Accepted: : 218
可爱
#557: alex9801
Accepted: : 217
#557: fast_photon
Accepted: : 217
#557: NineSuns
Accepted: : 217
#557: shinonome_ena
Accepted: : 217
#557: ucup-team5656
Accepted: : 217
有点小幽默
#557: yoy68
Accepted: : 217
#557: yuanshengnb
Accepted: : 217
#564: annyeong1
Accepted: : 216
#564: chenyx
Accepted: : 216
#564: diandian2020
Accepted: : 216
#564: frankly6
Accepted: : 216
#564: ucup-team7774
Accepted: : 216
#569: IvanZhang2009
Accepted: : 215
#569: jxy2012
Accepted: : 215
#569: rhineofts
Accepted: : 215
#569: ucup-team3862
Accepted: : 215
#569: ucup-team5248
Accepted: : 215
#569: ucup-team6852
Accepted: : 215
#569: ucup-team870
Accepted: : 215
#576: gg_gong
Accepted: : 214
Who am I? Why am I here?
#576: haze
Accepted: : 214
爱在一起或死在一起，舍此别无他途。
#576: infCraft
Accepted: : 214
#576: liangbowen
Accepted: : 214
#576: StefanSebez
Accepted: : 214
#576: ucup-team580
Accepted: : 214
#576: ucup-team7582
Accepted: : 214
#583: ucup-team3790
Accepted: : 213
#583: ucup-team8878
Accepted: : 213
#583: ucup-team8977
Accepted: : 213
#586: sherman2022
Accepted: : 212
#586: StarLzy
Accepted: : 212
#586: ucup-team4938
Accepted: : 212
乌龟风扇俱乐部
#589: Lzy_
Accepted: : 211
#589: pk661
Accepted: : 211
#589: ucup-team3966
Accepted: : 211
$$\underline{洹}我\underline{达}美\underline{乐}$$
#589: Wu_Ren
Accepted: : 211
#593: Silverwolf
Accepted: : 210