概率问题

复制代码 代码如下: <?php $setting = array( // 黑色概率 0 => 0.99, // 白色概率 1 => 0.01, ); // Requires the GD Library header("Content-type: image/png"); $im = imagecreatetruecolor(256, 256) or die("Cannot Initialize new GD image stream"); $w

<?php //计算抽奖的概率 function get_rand($proArr) { $result = ''; $proSum = array_sum($proArr); foreach ($proArr as $key => $proCur) { $randNum = mt_rand(1, $proSum); if ($randNum <= $proCur) { $result = $key; break; } else { $proSum -= $proCur; } } uns

神.上帝以及老天爷 http://acm.hdu.edu.cn/showproblem.php?pid=2048 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65536/32768 K (Java/Others) Problem Description HDU 2006'10 ACM contest的颁奖晚会隆重开始了! 为了活跃气氛,组织者举行了一个别开生面.奖品丰厚的抽奖活动,这个活动的具体要求是这样的: 首先,所有参加晚会的人员

10056 - What is the Probability ? Time limit: 3.000 seconds http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=115&page=show_problem&problem=997 Probability has always been an integrated part of computer algorith

10759 - Dice Throwing Time limit: 3.000 seconds http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=1700 n common cubic dice are thrown. What is the probability that the sum of all thr

10491 - Cows and Cars Time limit: 3.000 seconds http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=115&page=show_problem&problem=1432 In television contests, participants are often asked to choose one from a set

题目大意 初始有一个数字A0, 然后给出A1,A2..An共n个数字,这n个数字每个数字分别有一个操 作符,&,|,^ 且每个数字出现的概率是pi 如果某个数字出现了,那么就和前面的数字用 它的操作符进行位运算. 问最终的期望值是多少? 思路 这题官方题解说是反状态压缩 ,还是第一次做这种题. 知道了怎么表示状态这题就觉得不难做了,赛后1A. 题解官方的已 经很详细了,不再累赘: 反状态压缩--把数据转换成20位的01来进行运算 因为只有20位, 而且&,|,^都不会进位,那么一位一位地看

A Famous Game http://acm.hdu.edu.cn/showproblem.php?pid=4254 Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others) Problem Description Mr. B and Mr. M like to play with balls. They have many balls colored in blue and red. F

10169 - Urn-ball Probabilities ! Time limit: 3.000 seconds http://uva.onlinejudge.org/index.php?option=com_onlinejudge&Itemid=8&category=115&page=show_problem&problem=1110 看输出要求:The floating-point number indicates the probability that you

 这篇文章主要介绍了python概率计算器实现方法,实例分析了Python实现概率计算的技巧,具有一定参考借鉴价值,需要的朋友可以参考下     本文实例讲述了python概率计算器实现方法.分享给大家供大家参考.具体实现方法如下: ? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 from random import randrange #randrange form ra