1+ /**********************************************************************************
2+ * (Count the occurrences of numbers entered) Write a program that reads an *
3+ * unspecified number of integers and finds the one that has the most occurrences. *
4+ * The input ends when the input is 0. For example, if you entered 2 3 40 3 5 4 –3 *
5+ * 3 3 2 0, the number 3 occurred most often. If not one but several numbers have *
6+ * the most occurrences, all of them should be reported. For example, since 9 and *
7+ * 3 appear twice in the list 9 30 3 9 3 2 4, both occurrences should be reported. *
8+ **********************************************************************************/
9+ import java .util .*;
10+
11+ public class Exercise_21_06 {
12+ public static void main (String []args ) {
13+ // Create a Scanner
14+ Scanner input =new Scanner (System .in );
15+
16+ // Create a list and two sets
17+ List <Integer >list =new LinkedList <>();// Stores all integers
18+ TreeSet <Integer >set =new TreeSet <>();// Stores nonduplicate integers
19+ Set <Integer >results =new HashSet <>();// Stores results
20+
21+ // Prompt the user to enter a number of integers
22+ System .out .println ("Enter a number of integers."
23+ +"\n Input ends when the input is 0:" );
24+
25+ int integer ;
26+ while ((integer =input .nextInt ()) !=0 ) {
27+ list .add (integer );
28+ set .add (integer );
29+ }
30+
31+ // Find the maximum occurrence
32+ int max =0 ;
33+ for (Integer i :set ) {
34+ int frequency =Collections .frequency (list ,i );
35+ if (frequency >max )
36+ max =frequency ;
37+ }
38+
39+ // Add integers with the most occurrences to list
40+ for (Integer i :set ) {
41+ if (Collections .frequency (list ,i ) ==max )
42+ results .add (i );
43+ }
44+
45+ // Display the integers that have the most occurences
46+ if (results .size () >1 ) {
47+ System .out .println ("The integers that have the most occurrences are: "
48+ +results );
49+ }
50+ else
51+ System .out .println ("The integer that has the most occurrences is: "
52+ +results );
53+
54+ }
55+ }
