LuckySevens.java

   /*LuckySevens.java
   Simulate the game of lucky sevens until all funds are depleted.
   1) Rules:
           roll two dice
           if the sum equals 7, win $4, else lose $1
   2) The inputs are:
           the amount of money the user is prepared to lose
   3) Computations:
           use the random number generator to simulate rolling the dice
           loop until the funds are depleted
           count the number of rolls
           keep track of the maximum amount
   4) The outputs are:
           the number of rolls it takes to deplete the funds
           the maximum amount
   */
import java.util.Scanner;
import java.util.Random;
public class LuckySevens
{
  public static void main (String [] args)
  {
    Scanner reader = new Scanner(System.in);
    Random generator = new Random();

    int
      die1,             // die one
      die2,             // die two
      dollars,          // initial number of dollars (input)
      count,            // number of rolls to reach depletion
      maxDollars,       // maximum amount held by the gambler
      countAtMax;       // count when the maximum is achieved

      // Request the input
      System.out.print("How many dollars do you have? ");
      dollars = reader.nextInt();

      // Initialize variables
      maxDollars = dollars;
      countAtMax = 0;
      count = 0;

      // Loop until the money is gone
      while (dollars > 0)
      {
        count++;

        // Roll the dice.
        die1 = generator.nextInt (6) + 1; // 1-6
        die2 = generator.nextInt (6) + 1; // 1-6

        // Calculate the winnings or losses
        if (die1 + die2 == 7)
          dollars += 4;
        else
          dollars -= 1;

        // If this is a new maximum, remember it
        if (dollars > maxDollars)
        {
          maxDollars = dollars;
          countAtMax = count;
        }
      }

      // Display the results
      System.out.println("You are broke after " + count + " rolls.\n" +
                        "You should have quit after " + countAtMax +
                        " rolls when you had $" + maxDollars + ".");
    }
}