第二回 AtCoder Japan Open -予選- (AtCoder Regular Contest 207 (Div.1))
C
Combine to Make Non-decreasing
AtCoder
⌀ 2488
原题
← BD →
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Problem Statement

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You are given an integer sequence of length $N$, $A=(A_1, A_2, \cdots, A_N)$. Snuke wants to make $A$ a non-decreasing sequence.

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He can perform the following operation zero or more times.

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  • Choose two adjacent elements of $A$
  • Remove these two elements and insert the bitwise $\mathrm{OR}$ of these two values at the original position
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Find the maximum possible value of the length of $A$ when $A$ becomes a non-decreasing sequence.

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What is bitwise $\mathrm{OR}$? The bitwise $\mathrm{OR}$ of non-negative integers $A$ and $B$, $A\ \mathrm{OR}\ B$, is defined as follows. When $A\ \mathrm{OR}\ B$ is written in binary, the digit in the $2^k$ place ($k \geq 0$) is $1$ if at least one of the digits in the $2^k$ place of $A$ and $B$ written in binary is $1$, and $0$ otherwise. For example, $3\ \mathrm{OR}\ 5 = 7$ (in binary: $011\ \mathrm{OR}\ 101 = 111$).

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What is a non-decreasing sequence? A sequence $a=(a_1,a_2, \cdots, a_n)$ is a non-decreasing sequence if and only if $a_1 \le a_2 \le \ldots \le a_n$ holds.

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Constraints

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  • $1 \le N \le 2 \times 10^5$
  • $1 \le A_i <2^{30}$
  • All input values are integers.
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Input

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The input is given from Standard Input in the following format:

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N
A_1 A_2 \ldots A_N

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Output

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Print the answer.

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样例

Input #1
3
3 1 2
Output #1
2
- If the $1$-st and $2$-nd elements are chosen in the first operation, $A=(3,2)$ and $A$ is not a non-decreasing sequence. - If the $2$-nd and $3$-rd elements are chosen in the first operation, $A=(3,3)$ and $A$ is a non-decreasing sequence.
Input #2
4
4 1 2 3
Output #2
1
Input #3
20
105327673 847116534 928167271 478716741 244808645 744985167 772409400 950055714 32441819 24475691 74630537 632066724 170250355 937572655 791196964 469960355 264764288 1061830134 183233398 643628719
Output #3
7
题目信息
题号
arc207_c
时间限制
3 s
内存限制
1024 MB

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