JavaScript 24h to 12h converter

JavaScript

function convertTime(time){
  var arr = time.split(':'); //splits the string
  var hours = Number(arr[0]); 
  var minutes = Number(arr[1]);
  var AMPM = "";
  if(hours>=12 && hours != 24){ //checks if time is after 12 pm and isn't midnight
    hours = hours-12;
    AMPM = " pm";
  }else if(hours<12){//checks if time is before 12 pm
    AMPM = " am";
  }
  
  if(hours==24){//special case if it is midnight with 24
    hours = hours - 12;
    AMPM = " am"
  }
  
  if(hours==0){//special case if it is midnight with 0 
    hours = hours + 12;
  }
  
  //converts the Numbers back to a string
  var sHours = hours.toString();
  var sMinutes = minutes.toString();
  if(hours<10){//checks if the hours is 2 places long and adds a 0 if true
    sHours = "0" + sHours;
  }
  if(minutes<10){//checks if the minutes is 2 places long and adds a 0 if true
    sMinutes = "0" + sMinutes;
  }
  
  var result = sHours + ":" + sMinutes + AMPM; //sets string back together
  return result;
}
alert(convertTime("15:00"))