/**
 * Author: Josiah Yoder et al.
 * Class: SE1011-051
 * Lesson: Week 5, Day 1
 */
import java.util.Scanner;
import java.util.Random;
public class Example051_5_1 {
    public static void main(String[] ignored) {

        // Example of a very simple Pseudo-random number generator
        int max = 7;
        int increment = 4;
        int current = 0;
        for(int i=0;i<7;i++) {
            current+=increment;
            current%=max;
            System.out.println("Current value is: "+current);
        }

        // Using Java's random number generator
        Random generator = new Random();
        generator.setSeed(0); // This is so it always uses the same sequence.
        for(int i=0;i<10;i++) {
            int random = generator.nextInt(10);
            System.out.println("The "+i+"th random number is "+random);
        }

        // Scanner for the following examples
        Scanner in = new Scanner(System.in);

        // Raising a number to a power
        System.out.println("Please enter a number");
        double a = in.nextDouble();
        System.out.println("Please enter a second number");
        double b = in.nextDouble();
        System.out.println("a to the b is "+Math.pow(a,b));

        // First implementation of single-digit parsing
        // Checks that result is not -1 to see if it is a character
        // Works for all bases, but feels backwards.
        System.out.println("Please enter a number");
        String input = in.next();
        int len = input.length();
        if ( len > 1 ) {
            System.out.println("Sorry, that number is too long for me!");
        }
        else {
            char c;
            c = input.charAt(0);
            int result = Character.digit(c,16);
            if(result == -1) {
                System.out.println("Unrecognized digit");
            }
            else {
                System.out.println("Your number is "+result);
            }
        }

        // Second implementation of single-digit parsing
        // Uses Character.isDigit to test if it is a digit.
        // Cleaner, but works only for base 10
        System.out.println("Please enter a number");
        String input2 = in.next();
        int len2 = input2.length();
        if ( len2 > 1 ) {
            System.out.println("Sorry, that number is too long for me!");
        }
        else {
            char c;
            c = input2.charAt(0);
            if(!Character.isDigit(c)) {
                System.out.println("Unrecognized digit");
            }
            else {
                int result2 = Character.digit(c,10);
                System.out.println("Your number is "+result2);
            }
        }
    }
}