import java.util.ArrayList;
import java.util.Scanner;
import java.util.Collections;

public class Stats {

    public static ArrayList<Double> getInput() {
        ArrayList<Double> numbers = new ArrayList<>();
        Scanner in = new Scanner(System.in);

        boolean done = false;
        while (!done) {
            System.out.print("Enter a nunmber (-1 to stop): ");
            double next = in.nextDouble();
            if (next != -1) {
                numbers.add(next);
            } else {
                done = true;
            }
        }

        return numbers;
    }

    public static double mean(ArrayList<Double> numbers) {
        double sum = 0.0;
        for (Double d : numbers) {
            sum += d;
        }

        return sum / numbers.size();
    }

    public static double min(ArrayList<Double> numbers) {
        double smallest = numbers.get(0);

        for (Double d : numbers) {
            if (d < smallest) {
                smallest = d;
            }
        }

        return smallest;
    }

    public static double median(ArrayList<Double> numbers) {
        Collections.sort(numbers);
        System.out.println(numbers);

        // if the length is odd
        if (numbers.size() % 2 == 1) {
            int index = (numbers.size() - 1) / 2;
            return numbers.get(index);
        }
        // otherwise length is even
        else {
            double first = numbers.get(numbers.size() / 2 - 1);
            double second = numbers.get(numbers.size() / 2);
            return (first + second) / 2.0;
        }
    }

    public static void main(String args[]) {
        ArrayList<Double> numbers = getInput();
        System.out.println(numbers);

        System.out.println("Average = " + mean(numbers));
        System.out.println("Min = " + min(numbers));
        System.out.println("Median = " + median(numbers));


    }
}