Thread: Java array

Hi, I wrote this code, but the last part I did it by trial and error and by seeing something similar. I don't understand how to print the number of occurrences. I did it, but I don't understand why I had to put " if (array[i] > 0) "

/*PP 8.1 Design and implement an application that reads an arbitrary
      number of integers that are in the range 0 to 50 inclusive and
     counts how many occurrences of each are entered. After all input
    has been processed, print all of the values (with the number of
   occurrences) that were entered one or more times.
*/
    import java.util.*;
    public class arbArray
    {
        public static void main(String[]args)
        {
           final int FINAL=51;
           int[] array = new int[FINAL];
           Scanner scan = new Scanner(System.in);
 
          for (int i = 0; i < array.length; i++)
           { 
           System.out.println("Enter a number for location "+i+":");
           int n = scan.nextInt(); 
           while (n < 0 || n > 50) 
            { 
             System.out.println("Please enter a number between 0 and 50 for location "+i+" :"); 
               n = scan.nextInt(); 
             } 
              array[n]++; 
             }
            for (int i = 0; i < array.length; i++)
            { 
             if (array[i] > 0) 
            { 
 
              System.out.println(i + ": " + array[i]); // Print the number of occurrences for the numbers entered.
             }
          }
 
  }
}

Please read the Announcement topic at the top of the sub-forum to learn how to post your code correctly and other useful tips for newcomers.

This is a frequency counter. The last sentence of the assignment spec says, "print all of the values (with the number of occurrences) that were entered one or more times." That means, don't print frequencies of zero. That's why the statement you asked about is required.

Thanks, I hadn't seen the Announcement topic. I fixed now.

--- Update ---

Now I see it. I got it, thank you for your help. You said the magic words, "That means, don't print frequencies of zero." Sometimes is difficult to see it until someone gives you a hint.