Codeforces Round 717 (Div. 2)
D
Cut
Codeforces
2100
原题
← CE →
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This time Baby Ehab will only cut and not stick. He starts with a piece of paper with an array $a$ of length $n$ written on it, and then he does the following:

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  • he picks a range $(l, r)$ and cuts the subsegment $a_l, a_{l + 1}, \ldots, a_r$ out, removing the rest of the array.
  • he then cuts this range into multiple subranges.
  • to add a number theory spice to it, he requires that the elements of every subrange must have their product equal to their least common multiple (LCM).
翻译中…

Formally, he partitions the elements of $a_l, a_{l + 1}, \ldots, a_r$ into contiguous subarrays such that the product of every subarray is equal to its LCM. Now, for $q$ independent ranges $(l, r)$, tell Baby Ehab the minimum number of subarrays he needs.

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Input

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The first line contains $2$ integers $n$ and $q$ ($1 \le n,q \le 10^5$) — the length of the array $a$ and the number of queries.

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The next line contains $n$ integers $a_1$, $a_2$, $\ldots$, $a_n$ ($1 \le a_i \le 10^5$) — the elements of the array $a$.

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Each of the next $q$ lines contains $2$ integers $l$ and $r$ ($1 \le l \le r \le n$) — the endpoints of this query's interval.

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Output

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For each query, print its answer on a new line.

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Note

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The first query asks about the whole array. You can partition it into $[2]$, $[3,10,7]$, and $[5,14]$. The first subrange has product and LCM equal to $2$. The second has product and LCM equal to $210$. And the third has product and LCM equal to $70$. Another possible partitioning is $[2,3]$, $[10,7]$, and $[5,14]$.

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The second query asks about the range $(2,4)$. Its product is equal to its LCM, so you don't need to partition it further.

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The last query asks about the range $(3,5)$. You can partition it into $[10,7]$ and $[5]$.

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样例

Input #1
6 3
2 3 10 7 5 14
1 6
2 4
3 5
Output #1
3
1
2
InputCopy OutputCopy
题目信息
题号
1516D
时间限制
1 s
内存限制
256 MB
标签
二分
数据结构
动态规划
图论
数论
双指针

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。