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This assignment will give you practice with while loops and pseudorandom numbers.

Instructions

You are going to write a program that allows the user to play a guessing game in which your program "thinks up" an integer and allows the user to make guesses until the user gets it right with cues that indicate whether the secret number is higher or lower than each guess.

Methods

At a minimum, your program should have the following static methods in addition to method main:

• a method that introduces the game to the user
• a method to play one game with the user (just one game, not multiple games)
• a method to report overall results to the user

You may define more methods than this if you find it helpful, although you will find that the limitation that methods can return only one value will tend to limit how much you can decompose this problem.

Max Guess

You are to define a class constant for the maximum number used in the guessing game.

The sample output shows the user making guesses from 1 to 100, but the choice of 100 is arbitrary. By introducing a constant for 100, you should be able to change just the value of the constant to make the program play the game with a range of 1 to 50 or a range of 1 to 250 or some other range starting with 1.

Playing again

When you ask the user whether or not to play again, you should use the next() method of the Scanner class to read a one-word answer from the user.

You should continue playing if this answer begins with the letter y or the letter Y. Notice that the user is allowed to type words like yes. You are to look just at the first letter of the users response and see whether it begins with a y or n (either capitalized or not) to determine whether to play again.

Assume Good Input

Assume that the user always types an integer when guessing, that the integer is always in an appropriate range and that the user gives you a one-word answer beginning with y, Y, n or N when asked whether to play again.

End statistics

You will notice at the end of the output that you are to report various statistics about the series of games played by the user. You are to report

• the total number of games played,
• the total number of guesses made (all games included),
• the average number of guesses per game, and
• the best (fewest) number of guesses used in any single game.

The average number of guesses per games should be rounded to one decimal place (use printf).

Hints

Here are a few helpful hints to keep in mind.

• To deal with the yes/no response from the user, you will want to use some of the String class methods.
• You should use the next() method of the Scanner class to read a word from the console.
• Its a good idea to change the value of your class constant and run the program to make sure that everything works correctly with the new value of the constant. For example, turn it into a guessing game for numbers between 1 and 5.
• While you are developing your program, you might want to have it print out the answer before the user begins guessing. You dont want this in the final version of the program, but it can be helpful for you while you are developing the code.

Other Details

• You should handle the case where the user guesses the correct number on the first try. Print the following message: You got it right on the first guess!!
• In the last program you were asked to write very short methods that were no longer than 15 lines long and to have a very short main. This program is more difficult to decompose into methods, so you may end up having methods that are longer than 15 lines.
• You can also include more code in your main method than we allowed in the last program. In particular, you are required to have a while loop in main that plays multiple games and prompts the user for whether or not to play another game. Though, you shouldnt have all of the code in main because you are required to have the methods described at the beginning of this write-up.
• You are once again expect you to use good programming style:
  • Include useful comments throughout your program.
  • Make appropriate choices about when to store values as int versus double, which if/else constructs to use, what parameters to pass, and so on.
  • Use whitespace and indentation properly.
  • Limit lines to 100 characters.
  • Give meaningful names to methods and variables, and follow Java's naming standards.
  • Localize variables whenever possible.

Restrictions

Some students try to achieve repetition without properly using while loops, by writing a method that calls itself; this is not appropriate on this assignment and will result in a deduction in points

You also should not use more advanced topics that we have not covered in class. e.g. No use of Arrays, Lists, Classes

Sample Output

This program allows you to play a guessing game. It will think of a number between 1 and 100 and will allow you to guess until you get it. For each guess, It will tell you whether the correct answer is higher or lower than your guess. I'm thinking of a number between 1 and 100... Your guess? 50 It's lower. Your guess? 25 It's lower. Your guess? 12 It's lower. Your guess? 6 You got it right in 4 guesses Do you want to play again? y I'm thinking of a number between 1 and 100... Your guess? 50 It's lower. Your guess? 25 It's lower. Your guess? 12 It's higher. Your guess? 18 You got it right in 4 guesses Do you want to play again? YES I'm thinking of a number between 1 and 100... Your guess? 50 It's higher. Your guess? 75 It's lower. Your guess? 62 It's higher. Your guess? 68 It's lower. Your guess? 65 It's higher. Your guess? 66 It's higher. Your guess? 67 You got it right in 7 guesses Do you want to play again? nope Game statistics: total games = 3 total guesses = 15 guesses/game = 5.0 best game = 4