php抽奖程序，奖品可设置数量，中奖概率可调节

<?php

$prizes[] = ['probability' => 0.1, 'total' => 1, 'name' => '一等奖'];
$prizes[] = ['probability' => 1, 'total' => 1, 'name' => '二等奖'];
$prizes[] = ['probability' => 1, 'total' => 1, 'name' => '三等奖'];
$prizes[] = ['probability' => 1, 'total' => 1,'name' => '四等奖'];
$prizes[] = ['probability' => 96.9, 'total' => 100,'name' => '谢谢参与'];
// 模拟 100 次抽奖
for ($i = 1; $i <= 1000; $i++) {

// 计算每个奖品的中奖概率区间
$probabilityRanges = [];
$totalProbability = 0;
foreach ($prizes as $prize) {
$totalProbability += $prize['probability'];
$probabilityRanges[] = $totalProbability;
}
$randomNumber = mt_rand(1, $probabilityRanges[count($probabilityRanges) - 1]);
$prizeIndex = -1;
for ($j = 0; $j < count($probabilityRanges); $j++) {
if ($randomNumber <= $probabilityRanges[$j]) {
$prizeIndex = $j;
break;
}
}
if ($prizeIndex == -1) {
echo "第 $i 次抽奖，未中奖与\n";
continue;
}
$prize = $prizes[$prizeIndex];
if ($prize['total'] == 0) {
echo "第 $i 次抽奖，未中奖与\n";
continue;

}
$prizes[$prizeIndex]['total']--;

if ($prize === false) {
echo "第 $i 次抽奖，未中奖与\n";
} else {
echo "第 $i 次抽奖，中奖：".$prize['name']."-".$prize['total']."\n";
}

};

echo 'end';