How to get the value that appears the most often?

Question

    int[] nilai = {12,10,8,6,12,12,34,10,8,6,9,9,34,12,6,8,10,34,12,10,9,12};

    int[] frekuensi = new int[23];


    for (int i=0; i<nilai.length; i++) {
        frekuensi[i] = 0;
    }

    for (int i=0; i<nilai.length; i++) {
        frekuensi[nilai[i]]++;
    }

    int modus = 0;
    for (int i=0; i<nilai.length; i++) {
        if (frekuensi[i] > modus) {
            modus = i;
        }
    }        
    System.out.println("Nilai Modusnya = " + modus);

What? You're going to have to explain your problem a lot better than this. — Carcigenicate, May 08 '17 at 13:57
You're going to have to define "often" in this context. Appear more than average? Appear more than a given value? Appear more that its own value? Other...? — AntonH, May 08 '17 at 13:58
Possible duplicate of [Find the most popular element in int\[\] array](http://stackoverflow.com/questions/8545590/find-the-most-popular-element-in-int-array) — Ousmane D., May 08 '17 at 14:01
Values that often appear from the array above, the answer is 12 because appear in 6 times @AntonH — Rizky Ade Pratama Putra, May 08 '17 at 14:22

score 1 · Answer 1 · answered May 08 '17 at 14:00

There are several approaches to your problem:

Sort the array and count which is the number with more appearances
Use a map and count appearances for each distinct number (then, by iterating the map, you will easily find the most frequent one).
Use multiple loops (apparently this is what you are trying to do) to compute what's the most frequent number.

score 0 · Answer 2 · answered May 08 '17 at 14:41

Using Java 8 it is one-liner (not so readable). Explained in comments:

    int[] nilai = { 12, 10, 8, 6, 12, 12, 34, 10, 8, 6, 9, 9, 34, 12, 6, 8, 10, 34, 12, 10, 9, 12 };
    Integer maxKey = IntStream.of(nilai).boxed() // create an Stream from the int array
            .collect(Collectors.groupingBy(i -> i, Collectors.counting())) // count the occurrences of every number and convert it to map of (number, occurences)
            .entrySet().stream() // convert the map entries into stream
            .max((e1, e2) -> e1.getValue().compareTo(e2.getValue())) // obtain the map entry with largest occurrences count
            .map(Map.Entry::getKey).get(); // obtain the number that occurred the most often
    System.out.println(maxKey);

How to get the value that appears the most often?

2 Answers2