Codeforces Round 876 (Div. 2)
A
The Good Array
Codeforces
800
原题
←B →
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You are given two integers $n$ and $k$.

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An array $a_1, a_2, \ldots, a_n$ of length $n$, consisting of zeroes and ones is good if for all integers $i$ from $1$ to $n$ both of the following conditions are satisfied:

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  • at least $\lceil \frac{i}{k} \rceil$ of the first $i$ elements of $a$ are equal to $1$,
  • at least $\lceil \frac{i}{k} \rceil$ of the last $i$ elements of $a$ are equal to $1$.
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Here, $\lceil \frac{i}{k} \rceil$ denotes the result of division of $i$ by $k$, rounded up. For example, $\lceil \frac{6}{3} \rceil = 2$, $\lceil \frac{11}{5} \rceil = \lceil 2.2 \rceil = 3$ and $\lceil \frac{7}{4} \rceil = \lceil 1.75 \rceil = 2$.

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Find the minimum possible number of ones in a good array.

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Input

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Each test contains multiple test cases. The first line contains a single integer $t$ ($1 \le t \le 10^4$) — the number of test cases.

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The only line of each test case contains two integers $n$, $k$ ($2 \le n \le 100$, $1 \le k \le n$) — the length of array and parameter $k$ from the statement.

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Output

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For each test case output one integer — the minimum possible number of ones in a good array.

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It can be shown that under the given constraints at least one good array always exists.

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Note

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In the first test case, $n = 3$ and $k = 2$:

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  • Array $[ \, 1, 0, 1 \, ]$ is good and the number of ones in it is $2$.
  • Arrays $[ \, 0, 0, 0 \, ]$, $[ \, 0, 1, 0 \, ]$ and $[ \, 0, 0, 1 \, ]$ are not good since for $i=1$ the first condition from the statement is not satisfied.
  • Array $[ \, 1, 0, 0 \, ]$ is not good since for $i=1$ the second condition from the statement is not satisfied.
  • All other arrays of length $3$ contain at least $2$ ones.
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Thus, the answer is $2$.

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In the second test case, $n = 5$ and $k = 2$:

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  • Array $[ \, 1, 1, 0, 0, 1 \, ]$ is not good since for $i=3$ the second condition is not satisfied.
  • Array $[ \, 1, 0, 1, 0, 1 \, ]$ is good and the number of ones in it is $3$.
  • It can be shown that there is no good array with less than $3$ ones, so the answer is $3$.
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In the third test case, $n = 9$ and $k = 3$:

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  • Array $[ \, 1, 0, 1, 0, 0, 0, 1, 0, 1 \, ]$ is good and the number of ones in it is $4$.
  • It can be shown that there is no good array with less than $4$ ones, so the answer is $4$.
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In the fourth test case, $n = 7$ and $k = 1$. The only good array is $[ \, 1, 1, 1, 1, 1, 1, 1\, ]$, so the answer is $7$.

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样例

Input #1
7
3 2
5 2
9 3
7 1
10 4
9 5
8 8
Output #1
2
3
4
7
4
3
2
InputCopy OutputCopy
题目信息
题号
1839A
时间限制
1 s
内存限制
256 MB
标签
贪心
模拟
数学

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。