public ArrayList<Integer> mergeSort(ArrayList<Integer> list) {
long startTime = new Date().getTime(); //begin timer
ArrayList<Integer> temp = new ArrayList<Integer>(list); //make a new array from the other?
int first = 0;
int last = list.size() - 1;
mergeHelp(list, first, last, temp);
long endTime = new Date().getTime(); //get the end time
elapsedTime = endTime - startTime; //get the elapsed time by subtracting beginning from end
System.out.println("Time:" + elapsedTime); //print elapsed time
