Final Exam 1 and Final Exam Program

Code

    import java.util.Random;
    import java.util.Scanner;

public class FinalExam1
{
   
	public static void main( String[] args )
	{
		Scanner keyboard = new Scanner(System.in);
		Random rng = new Random();
        int heads = 0;
        int tails = 0; 
        int flips = 0;
        
            String coin;
            System.out.println( "How many times do you want to flip your coin? Make sure it is between 1 and 2,100,000,000" );
            int totalTries = keyboard.nextInt();
        //This while is for when the input is less than or greater than 21000000000 and it will ask for a new input between 1 and 2100000000.
        //If you input 2111111111111111111 the program wont run but if you put 2100000002 it is too high and will ask for an input.
        while ( totalTries < 1 || totalTries > 2100000000 )
        {
            System.out.println( "Make sure the number is between 1 and 2,100,000,000" );
            totalTries = keyboard.nextInt();
        }
        //do-while because it initializes the number of flips inside then does the while based on the number of flips
		do
		{
            
			int flip = rng.nextInt(2);
			if ( flip == 1 )
            {
            heads++;
            }
			if ( flip == 0 )
            {
            tails++;
            }
            flips++;
        //There are two variables flip and flips the flip is for the rng and flips counts the number of flips for probability     
		} while ( flips < totalTries);
        
        double probOfHeads = (double)heads / flips;
        double probOfTails = (double)tails / flips;        
        System.out.println("Out of " + flips + " flips " + heads + " came up heads and " + tails + " came up tails.");
        System.out.println("Probability of heads: " + probOfHeads );
        System.out.println("Probability of tails: " + probOfTails );
        //A good number to input that leads to a 50 50 most of the time is 200 if the number that is inputed is too big the probability would be 49.9999 and 50.0001 
        //or something very close and if it is too small the probability could be 100 and 0 if you only do 2 flips but close to 50 50 with a chance of exactly 50/50
        //I found to be 200.
        
         
	}
}
    

Picture of the output