Codeforces Round 775 (Div. 1, based on Moscow Open Olympiad in Informatics)
B
Integral Array
Codeforces
1800
原题
← AC →
翻译中…

You are given an array $a$ of $n$ positive integers numbered from $1$ to $n$. Let's call an array integral if for any two, not necessarily different, numbers $x$ and $y$ from this array, $x \ge y$, the number $\left \lfloor \frac{x}{y} \right \rfloor$ ($x$ divided by $y$ with rounding down) is also in this array.

翻译中…

You are guaranteed that all numbers in $a$ do not exceed $c$. Your task is to check whether this array is integral.

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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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The first line of each test case contains two integers $n$ and $c$ ($1 \le n \le 10^6$, $1 \le c \le 10^6$) — the size of $a$ and the limit for the numbers in the array.

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The second line of each test case contains $n$ integers $a_1$, $a_2$, ..., $a_n$ ($1 \le a_i \le c$) — the array $a$.

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Let $N$ be the sum of $n$ over all test cases and $C$ be the sum of $c$ over all test cases. It is guaranteed that $N \le 10^6$ and $C \le 10^6$.

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Output

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For each test case print Yes if the array is integral and No otherwise.

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Note

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In the first test case it is easy to see that the array is integral:

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  • $\left \lfloor \frac{1}{1} \right \rfloor = 1$, $a_1 = 1$, this number occurs in the arry
  • $\left \lfloor \frac{2}{2} \right \rfloor = 1$
  • $\left \lfloor \frac{5}{5} \right \rfloor = 1$
  • $\left \lfloor \frac{2}{1} \right \rfloor = 2$, $a_2 = 2$, this number occurs in the array
  • $\left \lfloor \frac{5}{1} \right \rfloor = 5$, $a_3 = 5$, this number occurs in the array
  • $\left \lfloor \frac{5}{2} \right \rfloor = 2$, $a_2 = 2$, this number occurs in the array
翻译中…

Thus, the condition is met and the array is integral.

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In the second test case it is enough to see that

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$\left \lfloor \frac{7}{3} \right \rfloor = \left \lfloor 2\frac{1}{3} \right \rfloor = 2$, this number is not in $a$, that's why it is not integral.

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In the third test case $\left \lfloor \frac{2}{2} \right \rfloor = 1$, but there is only $2$ in the array, that's why it is not integral.

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样例

Input #1
4
3 5
1 2 5
4 10
1 3 3 7
1 2
2
1 1
1
Output #1
Yes
No
No
Yes
InputCopy OutputCopy
Input #2
1
1 1000000
1000000
Output #2
No
InputCopy OutputCopy
题目信息
题号
1648B
时间限制
2 s
内存限制
512 MB
标签
暴力
构造
数据结构
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。