## 「ICPC Central Europe Regional Contest 2019」 G. K==S

Progressive hard octave rock tunes (so-called “phorts”) are written using a specifific music notation. This flflavor of rock is built on just 13 difffferent note pitches, other pitches (in other octaves)are considered to be an outdated musical ballast. Each note can be either a long one or a shortone. Consequently, there are exactly 26 difffferent notes in the rock.

## 「HDU 6185」Covering

Bob's school has a big playground, boys and girls always play games here after school.

To protect boys and girls from getting hurt when playing happily on the playground, rich boy Bob decided to cover the playground using his carpets.

Meanwhile, Bob is a mean boy, so he acquired that his carpets can not overlap one cell twice or more.

## 「LOJ 10222」 佳佳的Fibonacci

$T(n) = F(1) + 2\cdot F(2) + 3\cdot F(3) + \cdots n \cdot F(n);$
$T(x) \% m$ 的值

## 「SCOI2009」 迷路

windy在有向图中迷路了。 该有向图有 N 个节点，windy从节点 0 出发，他必须恰好在 T 时刻到达节点 N-1。 现在给出该有向图，你能告诉windy总共有多少种不同的路径吗？ 注意：windy不能在某个节点逗留，且通过某有向边的时间严格为给定的时间。