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A15588 | Uniform Chemistry

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内存限制256MB
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题目描述

In a parallel universe there are $n$ chemical elements, numbered from $1$ to $n$ . The element number $n$ has not been discovered so far, and its discovery would be a pinnacle of research and would bring the person who does it eternal fame and the so-called SWERC prize.

There are $m$ independent researchers, numbered from $1$ to $m$ , that are trying to discover it. Currently, the $i$ -th researcher has a sample of the element $s_i$ . Every year, each researcher independently does one fusion experiment. In a fusion experiment, if the researcher currently has a sample of element $a$ , they produce a sample of an element $b$ that is chosen uniformly at random between $a+1$ and $n$ , and they lose the sample of element $a$ . The elements discovered by different researchers or in different years are completely independent.

The first researcher to discover element $n$ will get the SWERC prize. If several researchers discover the element in the same year, they all get the prize. For each $i = 1, \, 2, \, \dots, \, m$ , you need to compute the probability that the $i$ -th researcher wins the prize.

输入格式

The first line contains two integers $n$ and $m$ ( $2 \le n \le 10^{18}$ , $1 \le m \le 100$ ) — the number of elements and the number of researchers.

The second line contains $m$ integers $s_1, \, s_2, \, \dots, \, s_m$ ( $1 \le s_i < n$ ) — the elements that the researchers currently have.

输出格式

Print $m$ floating-point numbers. The $i$ -th number should be the probability that the $i$ -th researcher wins the SWERC prize. Your answer is accepted if each number differs from the correct number by at most $10^{-8}$ .

输入输出样例

输入 #1
2 3
1 1 1
输出 #1
1.0 1.0 1.0
输入 #2
3 3
1 1 2
输出 #2
0.5 0.5 1.0
输入 #3
3 3
1 1 1
输出 #3
0.625 0.625 0.625
输入 #4
100 7
1 2 4 8 16 32 64
输出 #4
0.178593469 0.179810455 0.182306771
0.187565366 0.199300430 0.229356322
0.348722518
C++ 编辑器
输入
输出