시간 제한 | 메모리 제한 | 제출 | 정답 | 맞힌 사람 | 정답 비율 |
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2 초 | 1024 MB | 133 | 56 | 46 | 50.549% |
Bessie and Elsie are plotting to overthrow Farmer John at last! They plan it out over $N$ ($1\le N\le 2\cdot 10^5$) text messages. Their conversation can be represented by a string $S$ of length $N$ where $S_i$ is either $B$ or $E$, meaning the $i$th message was sent by Bessie or Elsie, respectively.
However, Farmer John hears of the plan and attempts to intercept their conversation. Thus, some letters of $S$ are $F$, meaning Farmer John obfuscated the message and the sender is unknown.
The excitement level of a non-obfuscated conversation is the number of times a cow double-sends - that is, the number of occurrences of substring $BB$ or $EE$ in $S$. You want to find the excitement level of the original message, but you don’t know which of Farmer John’s messages were actually Bessie’s / Elsie’s. Over all possibilities, output all possible excitement levels of $S$.
The first line will consist of one integer $N$.
The next line contains $S$.
First output $K$, the number of distinct excitement levels possible. On the next $K$ lines, output the excitement levels, in increasing order.
4 BEEF
2 1 2
9 FEBFEBFEB
2 2 3
10 BFFFFFEBFE
3 2 4 6