function groupByWeek(days) {
  const dates = days.map(a => new Date(a)).sort((a, b) => b - a);
  
  console.log(dates.map(a => (a.getMonth()+1) + "/" + a.getDate() + "/" + a.getFullYear()))

  let currentMonday = new Date();
  currentMonday.setDate(dates[0].getDate() - dates[0].getDay())
  
  let currentSunday = new Date()
  currentSunday.setDate(currentMonday.getDate() + 6);
  
  //console.log(firstMonday.getDay())
  //console.log(firstSunday.getDay())
  
  let weeks = []
  let currentWeek = []
  for(let date of dates) {
    if(date >= currentMonday && date <= currentSunday) {
      currentWeek.push((date.getMonth()+1) + "/" + date.getDate() + "/" + date.getFullYear())
    } else {
      if(currentWeek.length > 0) {
        weeks.push(currentWeek)
      }
      currentWeek = [(date.getMonth()+1) + "/" + date.getDate() + "/" + date.getFullYear()]
      currentMonday.setDate(date.getDate() - date.getDay())
      currentSunday.setDate(currentMonday.getDate() + 6);
    }
    
  }
  if(currentWeek.length > 0) {
    weeks.push(currentWeek)
  }
  
  return weeks;
  
}