Final Exam 1

Code

      /// Name: Alex Pinder
      /// Period: 5
      /// Program Name: Final Semester 1
      /// File Name: CoinFlip.java
      /// Date Complete: 1/20/16
      
      import java.util.Random;
      import java.util.Scanner;
      
      public class CoinFlip
      {
          public static void main ( String[] args )
          {
              Scanner keyboard = new Scanner(System.in);
              Random r = new Random();
              
              int times;
              
              do
              {
              System.out.print( "How many times will you flip the coin? " );
              times = keyboard.nextInt();
              
              if ( times <= 0 )
                System.out.println( "Choose a valid number" );
              if ( times > 2100000000 )
                System.out.println( "Choose a valid number" );
              } while ( times <= 0 || times > 2100000000 )
              
              int flip, counter;
              double timesHeads, timesTails;
              
              timesHeads = 0;
              timesTails = 0;
              counter = 0;
              
              while ( counter != times )// This doesn't actually have to be a do-while loop so i didn't use one.
              {
                  flip = 1 + r.nextInt(2);
                  
                  if ( flip == 1 )
                      timesHeads++;
                      
                  else if ( flip == 2 )
                      timesTails++;
                  
                  counter++;
                  
              }
              
              double probHeads = timesHeads / times;
              double probTails = timesTails / times;
              
              System.out.println( "\nYou flipped heads " + timesHeads + "  times and tails " + timesTails + " times.\n\nYou flipped heads " + (probHeads * 100) + "% of the time and tails " + (probTails * 100) + "% of the time." );
          }
      } // The number of flips you need to use to consistantly get as close to 50/50 is 2,100,000,000 because the more flips you loose the less likely it is to favor one side. 
    

Picture of the output