Question

You've devised a new twist on the traditional 'What number am I thinking of?' game to help your cousins learn their 7 times tables! Write a game that asks the user to guess the number you are thinking of. (For this game, the number will always be 42.)

The user is allowed 10 guesses, and makes a 'Mistake!' if they guess a number that isn't a multiple of 7. A user can make a maximum of one mistake, otherwise they lose the game. When the game is over, you should always print out That was fun.

Here is an example:

Guess a multiple of 7: 14

Nope!

Guess a multiple of 7: 32

Mistake! That number isn't a multiple of 7.

Guess a multiple of 7: 28

Nope!

Guess a multiple of 7: 86

Another mistake. Too bad.

That was fun.

​

Here is another example:

Guess a multiple of 7: 7

Nope!

Guess a multiple of 7: 14

Nope!

Guess a multiple of 7: 126

Nope!

Guess a multiple of 7: 133

Nope!

Guess a multiple of 7: 70

Nope!

Guess a multiple of 7: 77

Nope!

Guess a multiple of 7: 63

Nope!

Guess a multiple of 7: 35

Nope!

Guess a multiple of 7: 126

Nope!

Guess a multiple of 7: 77

Nope!

No guesses left!

That was fun.

​

If the user correctly enters 42, your program should print out You won! instead of Nope!, and then not ask for any more guesses. For example:

Guess a multiple of 7: 42

You won!

That was fun.

Answer 1

import java.util.Scanner;

public class GuessMultiple {

   public static void main(String[] args) {
       // Scanner class object to take user input
       Scanner scan= new Scanner(System.in);
      
       // Target value to be matched
       int targetNumber = 42;
       // Total guesses user get
       int totalGuesses = 10;
       // user input
       int guessedNumber = -1;
       // Total mistakes made by user
       int totalMistakes = 1;
      
       // Iterate loop till totalGuesses>0
       while(totalGuesses>0) {
           // Take user input
           // Decrement totalGuesses by 1
           System.out.print("Guess a multiple of 7: ");
           guessedNumber = scan.nextInt();
           totalGuesses--;
          
           // If number matched, print message and exit program
           if(guessedNumber==targetNumber) {
               System.out.println("You won!\nThat was fun.");
               System.exit(0);
           }
           // Else if, multiple of 7, display message
           else if(guessedNumber%7==0) {
               System.out.println("Nope!");
           }
           // If not multiple of 7 means first mistake
           // increment totalMistakes by 1 and print message
           else if(totalMistakes==1){
               System.out.println("Mistake! That number isn't a multiple of 7.");
               totalMistakes+=1;
           }
           // If totalMistakes is 2 means another mistake is made
           // Print message and exit
           else if(totalMistakes==2){
               System.out.println("Another mistake. Too bad.\nThat was fun.");
               System.exit(0);
           }
       }
       // After loop, means user lost and guesses are complete
       System.out.println("No guesses left!\nThat was fun.");
   }
}

OUTPUT-