Codeforces Round 664 (Div. 1)
E
Boboniu and Banknote Collection
Codeforces
3500
原题
← D→
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No matter what trouble you're in, don't be afraid, but face it with a smile.

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I've made another billion dollars!

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* — Boboniu*

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Boboniu has issued his currencies, named Bobo Yuan. Bobo Yuan (BBY) is a series of currencies. Boboniu gives each of them a positive integer identifier, such as BBY-1, BBY-2, etc.

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Boboniu has a BBY collection. His collection looks like a sequence. For example:

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image

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We can use sequence $a=[1,2,3,3,2,1,4,4,1]$ of length $n=9$ to denote it.

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Now Boboniu wants to fold his collection. You can imagine that Boboniu stick his collection to a long piece of paper and fold it between currencies:

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image

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Boboniu will only fold the same identifier of currencies together. In other words, if $a_i$ is folded over $a_j$ ($1\le i,j\le n$), then $a_i=a_j$ must hold. Boboniu doesn't care if you follow this rule in the process of folding. But once it is finished, the rule should be obeyed.

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A formal definition of fold is described in notes.

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According to the picture above, you can fold $a$ two times. In fact, you can fold $a=[1,2,3,3,2,1,4,4,1]$ at most two times. So the maximum number of folds of it is $2$.

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As an international fan of Boboniu, you're asked to calculate the maximum number of folds.

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You're given a sequence $a$ of length $n$, for each $i$ ($1\le i\le n$), you need to calculate the maximum number of folds of $[a_1,a_2,\ldots,a_i]$.

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Input

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The first line contains an integer $n$ ($1\le n\le 10^5$).

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The second line contains $n$ integers $a_1,a_2,\ldots,a_n$ ($1\le a_i\le n$).

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Output

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Print $n$ integers. The $i$-th of them should be equal to the maximum number of folds of $[a_1,a_2,\ldots,a_i]$.

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Note

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Formally, for a sequence $a$ of length $n$, let's define the folding sequence as a sequence $b$ of length $n$ such that:

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  • $b_i$ ($1\le i\le n$) is either $1$ or $-1$.
  • Let $p(i)=[b_i=1]+\sum_{j=1}^{i-1}b_j$. For all $1\le i \lt j\le n$, if $p(i)=p(j)$, then $a_i$ should be equal to $a_j$.
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($[A]$ is the value of boolean expression $A$. i. e. $[A]=1$ if $A$ is true, else $[A]=0$).

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Now we define the number of folds of $b$ as $f(b)=\sum_{i=1}^{n-1}[b_i\ne b_{i+1}]$.

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The maximum number of folds of $a$ is $F(a)=\max\{ f(b)\mid b \text{ is a folding sequence of }a \}$.

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样例

Input #1
9
1 2 3 3 2 1 4 4 1
Output #1
0 0 0 1 1 1 1 2 2
InputCopy OutputCopy
Input #2
9
1 2 2 2 2 1 1 2 2
Output #2
0 0 1 2 3 3 4 4 5
InputCopy OutputCopy
Input #3
15
1 2 3 4 5 5 4 3 2 2 3 4 4 3 6
Output #3
0 0 0 0 0 1 1 1 1 2 2 2 3 3 0
InputCopy OutputCopy
Input #4
50
1 2 4 6 6 4 2 1 3 5 5 3 1 2 4 4 2 1 3 3 1 2 2 1 1 1 2 4 6 6 4 2 1 3 5 5 3 1 2 4 4 2 1 3 3 1 2 2 1 1
Output #4
0 0 0 0 1 1 1 1 1 1 2 2 2 2 2 3 3 3 3 4 4 4 5 5 6 7 3 3 3 4 4 4 4 3 3 4 4 4 4 4 5 5 5 5 6 6 6 7 7 8
InputCopy OutputCopy
题目信息
题号
1394E
时间限制
1 s
内存限制
256 MB
标签
字符串

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