Codeforces Global Round 16
A
Median Maximization
Codeforces
800
原题
←B →
翻译中…

You are given two positive integers $n$ and $s$. Find the maximum possible median of an array of $n$ non-negative integers (not necessarily distinct), such that the sum of its elements is equal to $s$.

翻译中…

A median of an array of integers of length $m$ is the number standing on the $\lceil {\frac{m}{2}} \rceil$-th (rounding up) position in the non-decreasing ordering of its elements. Positions are numbered starting from $1$. For example, a median of the array $[20,40,20,50,50,30]$ is the $\lceil \frac{m}{2} \rceil$-th element of $[20,20,30,40,50,50]$, so it is $30$. There exist other definitions of the median, but in this problem we use the described definition.

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Input

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

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Each test case contains a single line with two integers $n$ and $s$ ($1 \le n, s \le 10^9$) — the length of the array and the required sum of the elements.

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Output

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For each test case print a single integer — the maximum possible median.

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Note

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Possible arrays for the first three test cases (in each array the median is underlined):

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  • In the first test case $[\underline{5}]$
  • In the second test case $[\underline{2}, 3]$
  • In the third test case $[1, \underline{2}, 2]$
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样例

Input #1
8
1 5
2 5
3 5
2 1
7 17
4 14
1 1000000000
1000000000 1
Output #1
5
2
2
0
4
4
1000000000
0
InputCopy OutputCopy
题目信息
题号
1566A
时间限制
1 s
内存限制
256 MB
标签
二分
贪心
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。