TestAddition.java

import java.math.BigInteger;
import java.util.Random;

public class TestAddition {
    public static void main(String[] args) {
        Random random = new Random();
        System.out.println("Size, Time(ns)");
        System.out.println("8, "+time(8,random));
        System.out.println("16, "+time(16, random));
        System.out.println("64, "+time(64,random));
        System.out.println("128, "+time(128,random));
        System.out.println("512, "+time(512,random));
        System.out.println("1024, "+time(1024,random));;
    }
    public static double time (int numBits,Random random) {
        StopWatch watch = new StopWatch().reset().start();
        int nTimes = 0;
        int a = 0;
        watch.stop().reset();

        while (watch.elapsed() < 0.01 || nTimes < 2) {
            // Setup a problem
            /** This constructor is more suitable as it allows us to generate random BigIntegers with a specific bit
            length (numBits). This constructor offers flexibility in creating BigIntegers with different bit lengths
            thus being more controlled.
             */
            BigInteger num1 = new BigInteger(numBits, random);
            BigInteger num2 = new BigInteger(numBits, random);

            // Run a problem - Measure the time for addition
            watch.start();
            BigInteger result = num1.add(num2);
            watch.stop();

            nTimes++;
        }
        return watch.elapsed() / nTimes ;
    }
}
// Oracle Java documentation for the BigInteger class - https://docs.oracle.com/javase/8/docs/api/java/math/BigInteger.html