text: function solve(year, month, day){
  
      let thisDay = new Date(year, month -= 1, day += 1);
   
      let newYear = thisDay.getFullYear();
      let newMonth = thisDay.getMonth();
      let newDate = thisDay.getDate();
   
      console.log(`${newYear}-${newMonth + 1}-${newDate}`);
  }
  
  
  
  solve(2019, 12, 31);