package numberreader;

import java.util.Scanner;

public class NumberReader {
    final static int MIN = 0;
    final static int MAX = 50;
    final static int NUMBERS = 20;

    private static final int[] numberList = new int[NUMBERS];
    private static final int[] occurences = new int[MAX + 1];


    public static int readInt(int min, int max) {
        Scanner input = new Scanner(System.in);
        int num;

        do {
            System.out.print("Enter a number between " + min + " and " + max + ": ");
            num = Integer.parseInt(input.nextLine());

            if (num < min || num > max) {
                System.out.print("Input out of range. ");
            }
        } while (num < min || num > max);

        return num;
    }

    public static int incrementOccurence(int num) {
        return ++occurences[num];
    }

    public static String occurencesTable() {
        String ret = "Inputs  Occurences\n";
        int rowsPrinted = 0;

        for (int number = 0; number < occurences.length; number++) {
            if (occurences[number] > 0) {
                ret += String.format("%-6d  %d\n", number, occurences[number]);
                rowsPrinted++;
            }
        }

        if (rowsPrinted == 0) {
            ret = "No numbers have been entered yet!\n";
        }

        return ret;
    }


    public static void main(String[] args) {
        int currentNumber;

        for (int i = 0; i < NUMBERS; i++) {
            currentNumber = readInt(MIN, MAX);
            numberList[i] = currentNumber;
            incrementOccurence(currentNumber);
        }

        System.out.println(occurencesTable());
    }

}