A15588. Uniform Chemistry
编程题
普及/提高-
知识点
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.
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.
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
说明/提示
In the first sample, all researchers will discover element $2$ in the first year and win the SWERC prize.
In the second sample, the last researcher will definitely discover element $3$ in the first year and win the SWERC prize. The first two researchers have a $50\%$ chance of discovering element $2$ and a $50\%$ chance of discovering element $3$ , and only element $3$ will bring them the prize.
In the third sample, each researcher has an independent $50\%$ chance of discovering element $3$ in the first year, in which case they definitely win the SWERC prize. Additionally, if they all discover element $2$ in the first year, which is a $12.5\%$ chance, then they will all discover element $3$ in the second year and all win the prize.
In the second sample, the last researcher will definitely discover element $3$ in the first year and win the SWERC prize. The first two researchers have a $50\%$ chance of discovering element $2$ and a $50\%$ chance of discovering element $3$ , and only element $3$ will bring them the prize.
In the third sample, each researcher has an independent $50\%$ chance of discovering element $3$ in the first year, in which case they definitely win the SWERC prize. Additionally, if they all discover element $2$ in the first year, which is a $12.5\%$ chance, then they will all discover element $3$ in the second year and all win the prize.