//Working version, generates all points, correct value of pie, FIXED maths on java:18
//Add comments for testing (up top) & on how program works (throughout program)

public class RandomlyCalculatingPie
{
        public static void main(String args[])
        {
                //using a long would be better in the long run but an int can have a max value of 2147M so an integer will do this time
                int circleCentreX = 0;
                int circleCentreY = 0;
                int liesInCircle = 0;
                double totalPoints = 1000000;
                int squareLength = 2;
                int halfSqLength = squareLength / 2;
                for(int i = 0; i < totalPoints; i++)
                {
                        double x = (Math.random() * squareLength)-(halfSqLength);
                        double y = (Math.random() * squareLength)-(halfSqLength);
                        if(Math.sqrt(Math.pow(x, 2D) + Math.pow(y, 2D)) <= halfSqLength)
                        {
                                //lies within the circle
                                liesInCircle++;
                        }
                }
                double estimatePie = (liesInCircle*4 / totalPoints);
                System.out.println("Pie: "+ estimatePie);
                System.out.println(liesInCircle + " points landed in the cirlce.");

        }

}