P. 100 Ex. 11.19

// Shavit Borisov
// CW

import java.util.Scanner;

public class Main {

    public static void main(String[] args)
    {
        Scanner in = new Scanner(System.in);
        ExactHit obj = new ExactHit();

        int current;

        System.out.printf("Enter a 4-digits number and hope to succeed! ");
        current = in.nextInt();

        while(!(obj.guess(current).equals("finished")))
        {
            System.out.printf("%s\n", obj.guess(current));
            System.out.printf("Keep trying! ");
            current = in.nextInt();
        }

        System.out.printf("%s", obj.guess(current));
        in.close();
    }
}

// Next class

import java.util.Random;

public class ExactHit
{
    private int[] numbers = new int[4];
    public ExactHit()
    {
        Random r = new Random();
        for(int i = 0; i < numbers.length; i++)
            numbers[i] = r.nextInt(10);
    }
    public String guess(int input)
    {
        int exacts = 0;
        int hits = 0;
        int currentNum;

        for(int i = 0; i < numbers.length; i++)
        {
            currentNum = input % 10;
            if(currentNum == numbers[i])
            {
                exacts++;
            }
            else
            {
                for(int j = 0; j < numbers.length; j++)
                {
                    if(j == i)
                        continue;
                    if(currentNum == numbers[j])
                    {
                        hits++;
                        break;
                    }
                }
            }
            input /= 10;
        }

        if(exacts == 4)
            return "finished";
        else
            return exacts + " exacts and " + hits + " hits";
    }
}