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QOJ 常见问题(Q&A) new by Qingyu 2023-03-23 22:14:28
QOJ 更新日志(2023 Mar) by Qingyu 2023-01-06 20:27:29
 
 
 
 
 
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#имя пользователяДевизЗадачи
/Qingyuღ花花ღ5520
1larryzhong820
2xiaowuc1you're a half a world away, but in my mind I whisper every single word you say517
3ZhaoZiLong403
4MaMengQi391
5HuangHanSheng384
6ZhangYiDe381
7GuanYunchang378
8hyddQingyu txdy $\\$ $\text{If my armor breaks, I’ll fuse it back together}$312
/flowersqytxdy!264
9Wu_Ren188
10Crysfly$$f(x)=(\sum_{i=0}^{n-1}\frac{y_i}{(x-q^i)\prod_{j\ne i}(q^i-q^j)})\prod_{i=0}^{n-1}(x-q^i)$$ 183
11repoman$$\prod_{i=0}^{n-1} (1+q^iz) = \sum_{i=0}^n q^{i(i-1)/2}\binom ni_q z^i$$176
12qwq$\displaystyle \sum_{i=1}^n [i,i+1,\cdots, i+k] \pmod{10^9+7}$169
13alpha1022$$\frac{1}{n_1!n_2!}(1-y)^{n_1+n_2+2} \left(\sum_{j\ge 0} y^j(t+j)^{n_1} \right) \left(\sum_{j\ge 0} y^j((j+1)-t)^{n_2} \right)$$162
14feecle6418gyh ak ioi159
15Lenstarorz Qingyu156
16zhouhuanyi153
17tricyzhkx149
18He_Ren148
19Sa3tElSefr146
20hutality$$[x^n](1-x)^{-\frac{1}{2}} \exp\left(\frac{x(1+x)}{2-2x}\right)\frac{\left(\frac{2-x}{2-2x}\right)^k}{k!}\cdot\,_0 F _1 \left(;k+1;x\left(\frac{2-x}{2-2x}\right)^2\right)$$138