js抽奖概率算法

class Lottery {
  constructor(prizes) {
    this.prizes = prizes; // 奖项数组，每个奖项包含名称和概率
  }

  draw() {
    const totalProbability = this.prizes.reduce((sum, prize) => sum + prize.probability, 0);
    let random = Math.random() * totalProbability;
    for (let prize of this.prizes) {
      if (random < prize.probability) {
        return prize.name;
      }
      random -= prize.probability;
    }
  }
}

// 示例奖项设置
const prizes = [
  { name: '一等奖', probability: 1 }, // 1% 中奖概率
  { name: '二等奖', probability: 5 }, // 5% 中奖概率
  { name: '三等奖', probability: 10 }, // 10% 中奖概率
  { name: '谢谢参与', probability: 84 } // 84% 中奖概率
];

const lottery = new Lottery(prizes);
console.log(lottery.draw()); // 随机输出一个奖项