Lottery_probability.php文件如何计算彩票中奖概率？

本文共计270个文字，预计阅读时间需要2分钟。

代码简化版：php$id=1;$prize='iphone6';$v=1;

$id=2;$prize='数码相机';$v=5;

$id=3;$prize='音箱设备';$v=10;

$id=4;$prize='50Q币';$v=24;

$id=5;$prize='10Q币';$v=60;

Lottery_probability.php

['id'=>1,'prize'=>'iphone6','v'=>1], '1' => ['id'=>2,'prize'=>'数码相机','v'=>5], '2' => ['id'=>3,'prize'=>'音箱设备','v'=>10], '3' => ['id'=>4,'prize'=>'50Q币','v'=>24], '4' => ['id'=>5,'prize'=>'10Q币','v'=>60], '5' => ['id'=>6,'prize'=>'1Q币','v'=>1900], ]; //每个奖品的中奖几率,奖品ID作为数组下标 foreach($prize_arr as $val){ $item[$val['id']] = $val['v']; } function get($item){ //中奖概率基数 $num = array_sum($item);//当前一等奖概率1/2000 foreach($item as $k=>$v){ //获取一个1到当前基数范围的随机数 $rand = mt_rand(1,$num); if($rand <= $v){ //假设当前奖项$k=2,$v<=5才能中奖 $res = $k; break; }else{ //假设当前奖项$k=6,$v>1900,则没中六等奖,总获奖基数2000-1900,前五次循环都没中则2000-1-5-10-24-60=1900,必中6等奖,哈哈 $num -= $v; } } return $res; } $res = get($item); $h = $prize_arr[$res-1]['prize']; echo $h.'; ';