Codeforces Round 1089 (Div. 2)
C1
A Simple GCD Problem (Easy Version)
Codeforces
1200
原题
← BC2 →
翻译中…

This is the easy version of the problem. The difference between the versions is that in this version, $1 \leq n \leq 2 \cdot 10^{5}$ and $b_i = a_i$ for $1 \leq i \leq n$. Note that a solution for one version does not necessarily solve the other version. You can hack only if you solved all versions of this problem.

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You are given two arrays $a$ and $b$ of length $n$.

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For each index $i$ ($1 \le i \le n$) of array $a$, you can perform the following operation at most once:

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  • choose an arbitrary integer $m$ ($\mathbf{m \neq a_i}$) such that $1 \leq m \le b_i$, and set $a_i := m$.
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Let the array after performing all the operations be $a'$. You can only perform operations in such a way that the following condition holds:

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  • for all $1\leq l \lt r\leq n$, $\operatorname{gcd}(a_l,a_{l+1},\ldots,{a_r})=\operatorname{gcd}(a'_l,a'_{l+1},\ldots,a'_r).$
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Here, $\gcd(x, y)$ denotes the greatest common divisor (GCD) of integers $x$ and $y$.

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You have to determine the maximum number of operations that can be performed while ensuring that the condition remains satisfied.

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Input

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Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^4$). The description of the test cases follows.

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The first line of each test case contains an integer $n$ ($2 \leq n \leq 2\cdot 10^5$) — the length of $a$.

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The following line of each test case contains $n$ space-separated integers $a_1, a_2, \ldots, a_n$ ($1 \leq a_i \leq 10^9$).

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The next line of each test case contains $n$ space-separated integers $b_1, b_2, \ldots, b_n$ ($\color{red}{b_i = a_i}$).

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It is guaranteed that the sum of $n$ over all test cases does not exceed $2\cdot10^5$.

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Output

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For each test case, output the maximum number of operations that can be done on a newline.

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Note

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For the first test case, the GCD of all subarrays is $1$. Hence, we can perform $6$ operations and change the array to $a' = [1, 1, 1, 1, 1, 1, 1]$. It can be shown that the maximum number of operations that can be performed in this case is $6$.

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For the second test case, note that all the values are equal, and reducing any value causes the GCD of subarrays to decrease. Hence, $0$ operations can be performed.

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For the third test case, it can be shown that at most $2$ operations can be performed.

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样例

Input #1
4
7
1 2 3 4 5 6 7
1 2 3 4 5 6 7
3
67 67 67
67 67 67
6
8 10 10 12 12 14
8 10 10 12 12 14
8
2 4 8 16 32 64 128 256
2 4 8 16 32 64 128 256
Output #1
6
0
2
1
InputCopy OutputCopy
题目信息
题号
2210C1
时间限制
2 s
内存限制
512 MB
标签
贪心
数论

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。