Question

I have a arraylist of type integer. The list contains some values.
At some point the list will contain similar values consecutively (3 values).
I need to find the position at which the 3 similar elements appear.

For example:

ArrayList<Integer> int_values=new ArrayList<Integer>();
int_values.add(10);
int_values.add(20);
int_values.add(30);
int_values.add(10);
int_values.add(10);
int_values.add(10);

As can be seen from position 3 to 5 there are similar values.
So I need to retrieve the position 5.
Also this series of similar elements repeating will occur only once.

I hope I am able to explain the scenario.

Answer 1

You can do as below,

public static List<Integer> findConsequtive3(ArrayList<Integer> int_values) {

        Integer[] arrayItems = (Integer[]) int_values.toArray(new Integer[0]);

        List<Integer> consequetive = new ArrayList<Integer>();
        int count = 1;
        for (int i = 1; i < arrayItems.length; i++) {
            if (arrayItems[i - 1] == arrayItems[i]) {
                count++;
                if (count == 3) {
                    consequetive.add(i + 1); // Since array is zero indexed adding 1
                    count = 0; // resetting count
                }
            }
        }
        return consequetive;
    }