School, 07.09.2017, Ex5, find average without max and min

public class Ex5 {
    // Write a Java program to compute the average value of an array of integers
    // except the largest and smallest values.
    public static void main(String[] args) {
        int[] arr = { 2, 100, 1, 20, 9 };

        int max = arr[0];
        int min = arr[0];
        int sum = 0;

        for (int i = 0; i < arr.length; i += 1) {
            sum += arr[i];

            if (arr[i] > max)
                max = arr[i];
            else if (arr[i] < min) {
                min = arr[i];
            }
        }

        double avg = (double) (sum - max - min) / (arr.length - 2);

        System.out.println("avg = " + avg);
    }

}