Based on these needs in the initial stage, and then based on the information on the Internet, a staged extraction method was adopted. Let’s take a look at the overall program: This program is completed under the ThinkPHP framework, using some frameworks to automatically I will explain the class libraries and functions provided one by one below, the controller part
The requirements that the lottery algorithm needs to meet are as follows:
1. You can control the probability of winning
2. Randomness
3. It is best to control the number of prizes
4. Limit the number of draws based on user ID or IP, mobile phone number, QQ number and other conditions
Based on these needs in the early stage, and then based on the information on the Internet, a staged extraction method was adopted. Let’s take a look at the overall procedure:
This program is completed under the ThinkPHP framework, using some class libraries and functions that come with the framework. I will explain them one by one below. The controller part:
The code is as follows | |
/** * * * @lanfengye */ class ChoujiangAction extends Action { //The start time of the lottery var $begin_time="2012-12-25 14:00:00"; //Start time 0-no limit //End time of the lottery var $stop_time="0"; //End time 0-no limit //The prize information for this lottery must be filled in in order from largest to smallest. id is the award number, prize is the winning information, v is the probability of winning, and num is the number of prizes //It should be noted that this must also contain information about not winning, and the probability is sorted from small to large var $prize_arr = array( '0' => array('id' => 1, 'prize' => 'Purchase 1G/year space for 44 yuan', 'v' => 1,'num'=>1), '1' => array('id' => 2, 'prize' => 'Purchase 1G/year space for 55 yuan', 'v' => 2, 'num'=>2), '2' => array('id' => 3, 'prize' => 'Purchase 1G/year space for 66 yuan', 'v' => 5,'num'=>2), '3' => array('id' => 4, 'prize' => 'Purchase 1G/year space for 77 yuan', 'v' => 10,'num'=>3), '4' => array('id' => 5, 'prize' => 'Purchase 1G/year space for 88 yuan', 'v' => 15,'num'=>4), '5' => array('id' => 6, 'prize' => 'Purchase 1G/year space for 99 yuan', 'v' => 67,'num'=>10), ); //How to display the home page Public function index(){ //Connect to the database to get the list of winners $Choujiang=M('Choujiang'); $this->assign('list', $Choujiang->where("rid>0")->order('id desc')->select()); unset($Choujiang); //Display the start time of the lottery on the homepage $this->assign('begin_time',$this->begin_time); $this->display(); } /** * Generate winning information, use ajax to request this method, and the customer needs to fill in the QQ number */ Public function make() { $qq_no= trim($_POST['qq_no']); import('ORG.Util.Input'); $qq_no=Input::getVar($qq_no); If(empty($qq_no)){ $this->ajaxReturn(1, 'Please fill in the QQ number correctly!'); exit; } If(!empty($this->begin_time) && time() $this->ajaxReturn(1, 'The lottery has not started yet, the starting time is:'.$this->begin_time); exit; } If(!empty($this->stop_time) && time()>strtotime($this->stop_time)){ $this->ajaxReturn(1, 'This lottery has ended, the end time is:'.$this->stop_time); exit; } //Get the award information array, from private members $prize_arr= $this->prize_arr; foreach ($prize_arr as $key => $val) { $arr[$val['id']] = $val['v']; } //$rid’s winning serial number $rid = $this->get_rand($arr); //Get the award id based on probability $str = $prize_arr[$rid - 1]['prize']; //Winning prize $Choujiang=M('Choujiang'); //Get the number of times a specific QQ number has participated in the lottery from the database. If it is greater than or equal to 3, the number of prompts has been exhausted If($Choujiang->where("qq_no='{$qq_no}'")->count()>=3){ $str='Your 3 lucky draw opportunities have been used up! '; $rid=0; //The number of times to obtain a specific award serial number from the database. If it is greater than or equal to the set maximum number of times, it will prompt that the prize has been drawn. If you need to always win the last commemorative award, just modify this place }elseif ($Choujiang->where("rid={$rid}")->count()>=$prize_arr[$rid-1]['num']) { $str='Sorry, the prize you have drawn has been exhausted! '; $rid=0; } // Generate a user lottery data for recording to the database $data=array( 'rid'=>$rid, 'pop'=>$str, 'qq_no'=>$qq_no, 'input_time'=>time() ); //Write the user lottery information array into the database $Choujiang->add($data); unset($Choujiang); //ajax return information $this->ajaxReturn(1, $str); } /** * Get the winning numbers based on probability */ Private function get_rand($proArr) { $result = ''; //Total probability accuracy of probability array $proSum = array_sum($proArr); //Probability array loop foreach ($proArr as $key => $proCur) { $randNum = mt_rand(1, $proSum); if ($randNum <= $proCur) { $result = $key; break; } else { $proSum -= $proCur; } } unset($proArr); return $result; } } ?> |
The algorithm is simple to use and has very good concurrent access performance. It can be used in various situations with slight modifications. Combined with user login and other information, it can effectively control the number of draws for each person. By changing the start and end to an array, you can complete the program to draw a lottery at a specific time every day.