2023.4.22 闲话

Dancin'

Get up on the floor
Dancin' all night long
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin'

All the time
My baby you on my mind
And I don't know why
Yeah but the feeling is fine
Can't you see
Honey you are for me
Though it weren't meant to be

Dancin' in the moonlight
Gazing at the stars so bright
Holding you until the sunrise
Sleeping until the midnight

Get up on the floor
Dancin' all night long
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin'

Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole
Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole

Everytime when I look in your eyes
I smile with pride happy that you're mine
Do you know, your love is true I know
You are the best thing that has happened to me

Get up on the floor
Dancin' all night long
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin'

Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole
Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole

Get up on the floor
Dancin' all night long
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin'

Oh
Get up on the floor
Dancin' all night long
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin' till the break of dawn
Get up on the floor
Dancin'

Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole
Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole

Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole
Dancin' is what to do
Dancin's when I think of you
Dancin's what clears my soul
Dancin's what makes me whole

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ABC295D. Three Days Ago

竟然能 XOR Hashing 做，标记一下标记一下 .

显然就是每个数出现偶数次，可以想到异或，每个数赋随机权值后扫描线查异或和为 0 的区间即可，时间复杂度 \(\Theta(n\log n)\) .

其实 \(x\) 赋成 \(2^x\) 就成常规状压做法了，所以其实本质相同（？

ABC295F. substr = S

\[\sum_{k=0}^nf(k)=\sum_{k=0}^n\sum_i[k\text{ 第 }i\text{ 位后包含 }S]=\sum_i[\text{不大于 }n\text{ 的第 }i\text{ 位后包含 }S\text{ 的整数个数}] \]

枚举 \(i\) 数位 DP 或者二分等，时间复杂度单次 \(\Theta(\operatorname{polylog}(r)\operatorname{polylog}(\lg r))\)，看实现优不优秀 .

ABC296E Transition Game

问题其实相当于基环内向树森林上走 . Takahashi 不难构造赢恰好环长次的方案，而不可能赢的次数比环长还多因为这时候 Aoki 直接拉满 \(K\) 就撞了 .

那么比较简单直接输出环长就完了时间复杂度 \(\Theta(n)\) .

ABC295G. Minimum Reachable City

操作可以看成缩 SCC，并查集维护，每次暴力并查集上跳，每个点最多缩一次，时间复杂度不算反 Ackermann 函数为 \(\Theta(n+q)\) .