php实现转盘游戏后台奖品按照概率发放

游戏转盘PHP后台实现奖品发放

<?php

header("Content-type:text/html;charset=GB2312");  //设置编码

//中奖奖品
$prizeArr = array(
    0 => array('id' => 1, 'prize' => '现金500W', 'v' => 1), //概率为1/200
    1 => array('id' => 2, 'prize' => 'iphone7', 'v' => 5),
    2 => array('id' => 3, 'prize' => '耐克跑鞋', 'v' => 10),
    3 => array('id' => 4, 'prize' => '魔声耳机', 'v' => 24),
    4 => array('id' => 5, 'prize' => '蓝牙音响', 'v' => 60),
    5 => array('id' => 6, 'prize' => '现金1元', 'v' => 100)
);

/*
 * 对数组进行处理
 */
$item = [];
foreach ($prizeArr as $k => $v) {
    //使用新数组item
    $item[$v['id']] = $v['v'];
}
/*
 array(
        1 => 1,
        2 => 5,
        3 => 10,
        4 => 24,
        5 => 60,
        6 => 100
     );
 */

function getRand($item)
{
    $num    = array_sum($item);//计算出分母200
    $result = 0;
    foreach ($item as $k => $v) {
//        var_dump('k = ' . $k . ',    v=' . $v);
//        var_dump('<br><br>');
        $rand = mt_rand(1, $num);//概率区间(整数) 包括1和200
//        var_dump('随机数=' . json_encode($rand));
//        var_dump('<br><br>');
        /*
         *这个算法很666
         */
        if ($rand <= $v) {
            //循环遍历,当下标$k = 1的时候，只有$rand = 1 才能中奖
            $result = $k;
//            echo '$rand <= $v      ,' . $rand . '--' . $v;
//            var_dump('<br><br>');
            break;
        } else {
            //当下标$k=6的时候，如果$rand>100 必须$rand < = 100 才能中奖 ，那么前面5次循环之后$rand的概率区间= 200-1-5-10-24-60 （1,100） 必中1块钱
            $num -= $v;
//            echo '      *' . $rand . '*     num=' . $num;
//            var_dump('<br><br>');
        }
    }

//    var_dump('$result=' . json_encode($result));
//    var_dump('<br><br>');
    return $result;
}


$times  = 5000000;
$prizes = [];
for ($i = 0; $i < $times; $i++) {
    $r = getRand($item);
    $p = $prizeArr[$r - 1]['prize'];
    if (isset($prizes[$p])) {
        $num = $prizes[$p];
        $num++;
        $prizes[$p] = $num;
    } else {
        $prizes[$p] = 1;
    }
    //    var_dump(gettype($prizes));
    //    break;
}

var_dump('概率：');
var_dump($prizes);
var_dump('<br><br>');
foreach ($prizes as $p => $nums) {
    var_dump($p . '------>' . $nums / $times);
    var_dump('<br><br>');
}
var_dump('<br><br>');
var_dump('<br><br>');
foreach ($item as $p => $nums) {
    var_dump($prizeArr[$p - 1]['prize'] . '------>' . $nums / 200);
    var_dump('<br><br>');
}