/**
 * Calculate the value of pi by simulating throwing darts at a dart board.
 *
 * @author Wes Mills
 * @version 11/18/18
 */
import java.util.Scanner;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
public class EstimatePi
{
    public static int[] dartSuccesses(int z, int numOfDarts, int numOfTrials)
    {
        int counter = 0;
        int counter2 = 0;
        int index = 0;
        int[] trials = new int [numOfTrials];
        for(int t = 0; counter < numOfTrials; counter++) //Counts number of trials done
        {
            for(z = 0; counter2 < numOfDarts; counter2++) //Simulates amount of time dart would hit the board, randomly
            {
                double x = Math.pow(Math.random(), 2);
                double y = Math.pow(Math.random(), 2);
                if(x + y <= 1)
                {
                    z++;
                }
            }
            trials[index] = z;
            index++;
        }
        return trials; //z being the number of times the dart hit the board
    }

    public static double dartAverage(int[] dartHits) //Estimates what pie is based on average of results
    {
        double dartAvg = 0.0;
        int counter = 0;
        for(int darts : dartHits)
        {
            dartAvg += dartAvg;
            counter++;
        }
        dartAvg /= counter;
        return dartAvg;
    }


    public static void main(String[] args)throws IOException
    {
        Scanner in = new Scanner(System.in);
        int counter = 1;

        System.out.println("Please enter the number of darts you'd like to see estimated per trial.");
        int dartCount = in.nextInt();
        System.out.println("Please enter the amount of trials you'd like to see.");
        int trialCount = in.nextInt();

        int hits = 0;
        int[] dartHits = dartSuccesses(hits, dartCount, trialCount);
        double piEstimate = dartAverage(dartHits);

        //Output
        System.out.println("\nHow many darts per trial? " + dartCount);
        System.out.println("\nHow many trials? " + trialCount);
        System.out.println("");
        for(int index = 0; index < trialCount; index++)
        {
            System.out.printf("%0s%0d%0s%10d%n", "Trial [ ", counter, "]: pi = ", dartHits[index]);
            counter++;
        }
        System.out.printf("%0s%10d" , "Estimate of pi = ", piEstimate);
    }
}