blah#1594's "Dorky" Challenge

challenge.java

/*
 * RULES
 *0)  Store the number 16022236204009818131831320183.
 *1)  Calculate the last 6 digits of the number.
 *2)  Calculate the value of the last 16 bits of the number.
 *3a) Generate a new random number > 1,000,000.
 *3b) Take the last 6 digits of the random number, and the value represented by the last 16 bits of it as well. Add their sum to a cumulative score.
 *3c) Repeat step 3 until program runs for 1 second.
 *4)  Report the total score.

 *(1) and (2) must be correct (320183, 61047).
 *Score should be at least 2,000,000,000,000.
 */

package com.mrkelpy.test;

import com.google.gson.Gson;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;

import java.math.BigInteger;
import java.sql.Timestamp;
import java.time.Instant;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;

public class Main {

    public static void main(String[] args) {

        // Declare useful variables for later usage
        BigInteger number = new BigInteger("16022236204009818131831320183");
        BigInteger eval = new BigInteger("200000000000");
        Random rand = new Random();
        int million = (int) Math.pow(10, 6);

        // Get the last digits of the number, aswell as the value for the last 16 bits
        int lastDigits = number.mod(BigInteger.valueOf((million))).intValueExact();
        int last16BitsValue = Integer.parseInt(
                Integer.toBinaryString(number.intValue()).substring(Integer.toBinaryString(number.intValue()).length() - 16), 2);

        // Create the score, and get a timestamp roughly 1 second into the future
        BigInteger score = BigInteger.valueOf(last16BitsValue).add(BigInteger.valueOf(lastDigits));
        Timestamp ts = new Timestamp(System.currentTimeMillis() + 1000);

        // Repeat the step of essentially repeating what we did before, but with a random number
        // with a lower bound of 1 million, for 1 second
        while (ts.compareTo(Timestamp.from(Instant.now())) > 0) {

            int randnum = rand.nextInt(million) + million;
            int last16BitsOfRandValue = Integer.parseInt(
                    Integer.toBinaryString(randnum).substring(Integer.toBinaryString(randnum).length() - 16), 2);
            int last6DigitsOfRand = randnum % (int) Math.pow(10, 6);

            score = score.add(BigInteger.valueOf(last6DigitsOfRand + last16BitsOfRandValue));
        }

        // Print the score and whether the challenge was completed.
        System.out.println(score);
        if (score.compareTo(eval) > 0) System.out.println("passed!");
        else System.out.println("failed");

    }
}