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As a traditional event in the past years, join the IOI 2026 Prediction Game!
الأعلى تقييماً المقبولة
#393: huangleyi
Accepted: : 232
#393: Prime
Accepted: : 232
#393: ucup-team4269
Accepted: : 232
#397: 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
#397: moriko
Accepted: : 231
#397: ucup-team3586
Accepted: : 231
#397: ucup-team5984
Accepted: : 231
#397: ucup-team6748
Accepted: : 231
#402: lnw143
Accepted: : 230
what doesn't kill you makes you stronger
#402: ucup-team5008
Accepted: : 230
#404: Calculatelove
Accepted: : 228
Love all my perfect imperfections.
#404: 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。
#404: zhenghanyun
Accepted: : 228
#407: cmll02
Accepted: : 227
#408: chenshi
Accepted: : 226
#408: oldcatsthecat
Accepted: : 226
#410: feecle6418
Accepted: : 225
gyh ak ioi
#410: ucup-team7713
Accepted: : 225
#410: zzzYheng
Accepted: : 225
你好我的朋友
#413: kangleni
Accepted: : 224
#413: SoyTony
Accepted: : 224
真実はいつもひとつ
#413: Wansur
Accepted: : 224
#416: 8BQube
Accepted: : 223
#416: ucup-team2819
Accepted: : 223
#418: liyelin
Accepted: : 222
#418: ucup-team7678
Accepted: : 222
#420: 2147483647str
Accepted: : 221
#420: ucup-team2262
Accepted: : 221
#422: ucup-team7643
Accepted: : 220
#422: ucup-team7796
Accepted: : 220
#424: masterhuang
Accepted: : 219
不要逃避自己的命运
#424: ucup-team4478
Accepted: : 219
#424: xlwang
Accepted: : 219
#427: binminh01
Accepted: : 218
#427: hcywoi
Accepted: : 218
#427: kjhhjki
Accepted: : 218
#430: alex9801
Accepted: : 217
#430: Arkweedy
Accepted: : 217
#430: houzhiyuan
Accepted: : 217
#430: shinonome_ena
Accepted: : 217
#430: ucup-team5656
Accepted: : 217
有点小幽默
#430: ucup-team7701
Accepted: : 217
#436: fast_photon
Accepted: : 216
#436: rhineofts
Accepted: : 216
#436: tryandtryagain
Accepted: : 216
#436: ucup-team6852
Accepted: : 216
#440: bykem
Accepted: : 215
#440: gg_gong
Accepted: : 215
Who am I? Why am I here?
#440: infCraft
Accepted: : 215
#440: jxy2012
Accepted: : 215
#440: ucup-team3862
Accepted: : 215
#440: ucup-team7733
Accepted: : 215
#440: ucup-team870
Accepted: : 215
#447: StefanSebez
Accepted: : 214
#447: ucup-team580
Accepted: : 214
#447: ucup-team7102
Accepted: : 214
#447: ucup-team7582
Accepted: : 214
#451: sherman2022
Accepted: : 213
#451: ucup-team3790
Accepted: : 213
#453: ucup-team073
Accepted: : 212
#453: ucup-team4938
Accepted: : 212
乌龟风扇俱乐部
#455: pk661
Accepted: : 211
#455: ucup-team3966
Accepted: : 211
$$\underline{洹}我\underline{达}美\underline{乐}$$
#455: ucup-team7774
Accepted: : 211
#455: Wu_Ren
Accepted: : 211
#455: YMH_fourteen
Accepted: : 211
$$4+9+19+10+15+9+14+20=\mathbf{100}$$
#460: C1942huangjiaxu
Accepted: : 210
#460: IvanZhang2009
Accepted: : 210
#460: ucup-team228
Accepted: : 210
#460: yoy68
Accepted: : 210
#460: yzhang
Accepted: : 210
如果结果不如你所愿，就在尘埃落定前奋力一搏
#465: do_while_true
Accepted: : 209
#465: jinqihao2023
Accepted: : 209
#465: Lzy_
Accepted: : 209
#468: KnownError_
Accepted: : 207
#468: mod998244353
Accepted: : 207
#468: ucup-team123
Accepted: : 207
#471: cyx
Accepted: : 206
#471: juan_123
Accepted: : 206
#473: ucup-team7255
Accepted: : 205
#474: Federal1Commander
Accepted: : 204
#474: frankly6
Accepted: : 204
#474: happybob
Accepted: : 204
#474: oceeff
Accepted: : 204
#474: yyyyxh
Accepted: : 204
What is OI (O_o)?
#479: atm10
Accepted: : 203
The more we love the woman the more we less more more
#479: ucup-team1565
Accepted: : 203
#479: Yarema
Accepted: : 203
#482: diandian2020
Accepted: : 202
#482: new_dawn_2
Accepted: : 202
#482: NineSuns
Accepted: : 202
#482: ucup-team3634
Accepted: : 202
#486: liujunyi123
Accepted: : 201
#486: mln
Accepted: : 201
#486: nealzane
Accepted: : 201
#486: ucup-team1617
Accepted: : 201
#490: ucup-team1055
Accepted: : 200
#490: ucup-team3774
Accepted: : 200
#490: ucup-team7235
Accepted: : 200
#493: caijianhong
Accepted: : 199