使用‘’switch‘语句显示星期几。(问题)

function displayWeekday(day) {
  let weekday;

  switch (day) {
    case 1:
      weekday = "星期一";
      break;
    case 2:
      weekday = "星期二";
      break;
    case 3:
      weekday = "星期三";
      break;
    case 4:
      weekday = "星期四";
      break;
    case 5:
      weekday = "星期五";
      break;
    case 6:
      weekday = "星期六";
      break;
    case 7:
      weekday = "星期日";
      break;
    default:
      weekday = "无效的输入";
  }

  console.log(weekday);
}

displayWeekday(3);  // 输出：星期三