"count" in Arrays?

Question

I have a question, my professor posted this question:
Write the body of the method select, shown below. The method traverses
the array arr and prints out all numbers that are both greater than or equal
to low and less than or equal to high.
For example, for the array below,
double[] a = { 2.0, 3.5, 6.8, 7.2, -10.0, 5.2, 16.3};
the call
select(a, 3.0, 7.0);
will print the numbers in a >= 3.0 and <= 7.0, i.e.
3.5
6.8
5.2
He then posted the answer:
      // print all items of arr between low and high, including
      // the borders
      public static void select(double[] arr, double low, double high)
          // print a title
          System.out.println("The items of the array >= " + low +
               " and <= " + high);
          // check  for empty array
          if (arr == null || arr.length == 0)
              System.out.println("The array is empty.");
              return;
          // we use an enhanced loop
          // we use a count to print the position of the number
          // in the sequence of numbers that satisfy that condition
          int count = 0;
          for ( double c: arr)
             // check if low <= c <= high
             if ( low <= c && c <= high)
                 count++;
                 System.out.println(count + ". " + c);
      } // end methodI understood everything except for "count" why exactly is count needed? Also, I don't get the output, did he make a mistake? Does it print the count number a period and the array number?

Answer 1

MiamiLoco wrote:
I understood everything except for "count" why exactly is count needed? Also, I don't get the output, did he make a mistake? Does it print the count number a period and the array number?Bingo. The count is simply for printing where in the array the number is. It's the same as doing this:
for(int i = 0; i < arr.length; i++){
   if ( low <= arr[i] && arr[i] <= high)
      System.out.println(i + ". " + arr);
}or for ( double c: arr){
// check if low <= c <= high
if ( low <= c && c <= high)
count++;
// System.out.println(count + ". " + c);
System.out.println("The number " + c + " is in the range and located in position " + count);
}The teacher's code wouldn't generate the same exact output he asked for, but it gets the job done.
Question: why didn't you ask the teacher about this bit? It's generally better to ask him than us!