php抽奖概率根据人数变

<?php
// 假设有三个奖项，分别是：一等奖、二等奖、三等奖
$prizes = [
    '一等奖' => 0.01, // 1%
    '二等奖' => 0.05, // 5%
    '三等奖' => 0.94  // 94%
];

// 参与人数
$participants = 100;

// 计算每个奖项的中奖概率
$totalProbability = array_sum($prizes);
foreach ($prizes as $prize => $probability) {
    $prizes[$prize] = ($probability / $totalProbability) * 100;
}

// 模拟抽奖
$winningPrize = null;
$randNumber = mt_rand(1, 100);

foreach ($prizes as $prize => $probability) {
    if ($randNumber <= $probability) {
        $winningPrize = $prize;
        break;
    }
    $randNumber -= $probability;
}

echo "恭喜你获得了: " . $winningPrize;
?>