# FinalExam: CoinProbability

## Code

/// Name: Jason Kim
/// Period: 7
/// Program Name: CoinProbability
/// File Name: CoinProbability.java
/// Date Finished:1/21/16
import java.util.Scanner;
import java.util.Random;
public class CoinProbability
{
public static void main(String[] args)
{
Scanner keyboard = new Scanner(System.in);
Random r = new Random();
int flipCounter = 0, tails = 0, heads = 0, flip;//tails: number of tails, heads = number of heads,flip: the number of flips the user wants to do
do
{
System.out.println("\nPlease choose a number between 0 and 2,100,000,000.");
System.out.print("\nHow many times do you want to flip? ");
flip = keyboard.nextInt();
}while( flip> 2100000000 || flip < 1);//checks if the number is between 1 and 2100000000
while( flipCounter < flip)
{
int side = r.nextInt(2);
//0 = tail, 1 = head
if( side == 0)
{
tails ++;
}
else
{
heads++;
}
flipCounter++;
}
double probOfHeads = (double)heads / flip;
double probOfTails = (double)tails / flip;
System.out.println("number of heads: " + heads);
System.out.println("number of tails: " + tails);
System.out.println("\nprobability of rolling heads: " + probOfHeads);
System.out.println("probability of rolling tails: " + probOfTails);
System.out.println();
}
}
//The bigger the number of times you flip, the probability of getting heads( or tails) gets closer to 50%
//If you put in 2,100,000,000 you will get a probability that is close to 50%.

### Picture of the output