//Importing Resources (Random)
import java.util.Random;
//Importing Resources (Scanner)
import java.util.Scanner;
public class Assignment2 {
/**
* Scanner used for input within program
*/
public static Scanner scanner = new Scanner(System.in);
/**
* Main method that provides user with a menu in which each number
* represents a different method (e.g addtion) that they can carry out
*/
public static void main(String[] args) {
try {
// Declare variable for user's option and defaulting to 0
int menuOption = 0;
do {
// Setting menuOption equal to return value from showMenu();
menuOption = showMenu();
// Switching on the value given from user
switch (menuOption) {
case 1:
add();
break;
case 2:
subtract();
break;
case 3:
guessRandomNumber();
break;
case 4:
printLoop();
break;
case 5:
System.out.println("Quitting Program...");
break;
default:
System.out.println("Sorry, please enter valid Option");
}// End of switch statement
} while (menuOption != 5);
// Exiting message when user decides to quit Program
System.out.println("Thanks for using this Program...");
} catch (Exception ex) {
// Error Message
System.out.println("Sorry problem occured within Program");
// flushing scanner
scanner.next();
} finally {
// Ensuring that scanner will always be closed and cleaning up
// resources
scanner.close();
}
}// End of main Method
/**
* Method that prints menu to screen and gets returns user's option from menu
* @return Returns user Option
*/
public static int showMenu() {
// Declaring var for user option and defaulting to 0
int option = 0;
// Printing menu to screen
System.out.println("Menu:");
System.out.println("1.Add");
System.out.println("2.Subtract");
System.out.println("3.Guess a Random Number");
System.out.println("4. Print many times");
System.out.println("5. Quit Program");
// Getting user option from above menu
System.out.println("Enter Option from above...");
option = scanner.nextInt();
return option;
}// End of showMenu
/**
* Method that adds two random numbers (from 1-100) and take a user guess
* for the addition.Then outputs certain statements dependent if user guess
* is correct or not.
*/
public static void add() {
// Setting up new random
Random random = new Random();
// Declaring Integers
int num1;
int num2;
int result;
int input;
//defaulting input to 0
input = 0;
// Declaring boolean for valid user answer (Defaulted to false)
boolean validAnswer = false;
//Declaring boolean for correct user answer (default to false)
boolean correctAnswer=false;
do {
// Create two random numbers between 1 and 100
num1 = random.nextInt(100);
num1++;
num2 = random.nextInt(100);
num2++;
//Do while loop that loops until user gives valid input
do {
//validAnswer set to true to avoid infinite loop
validAnswer = true;
// Displaying numbers for user and getting user input for answer
System.out.println("Adding numbers...");
System.out.printf("What is: %d + %d? Please enter answer below", num1,num2);
result = num1 + num2;
try {
input = scanner.nextInt();
} catch (Exception ex) {
// Print error message
System.out.println("Sorry, Invalid entry for Addition...Please Retry!");
// flush scanner
scanner.next();
validAnswer = false;
}
} while (!validAnswer);
// Line break for code clarity
System.out.println();
// if else statement to determine if answer is correct
if (result == input) {
System.out.println("Well done, you guessed corectly!");
correctAnswer = true;
} else {
System.out
.println("Sorry incorrect, Please guess another Addition");
correctAnswer = false;
}
} while (!correctAnswer);
}// End of add
/**
* Method that subtracts two random numbers (from 1-100) and takes a user
* guess for the subtraction. Then outputs certain statements dependent if
* user guess is correct or not.
*/
public static void subtract() {
// Setting up random
Random random = new Random();
// Declaring Integers
int num1;
int num2;
int result;
int input;
//set input to 0
input = 0;
// Declaring boolean for validity of userAnswer (Defaulted to false)
boolean validAnswer = false;
//Declaring boolean for correct user answer (default to false)
boolean correctAnswer=false;
do {
// Create two random numbers between 1 and 100
num1 = random.nextInt(100);
num1++;
num2 = random.nextInt(100);
num2++;
do {
// Set correctAnwer to true to avoid infinite iterations
validAnswer = true;
// Displaying numbers for user and getting user input for answer
System.out.println("Subtracting numbers...");
System.out.printf("What is: %d - %d? Please enter answer below", num1,num2);
result = num1 - num2;
try {
input = scanner.nextInt();
} catch (Exception ex) {
// Print error message
System.out.println("Sorry, Invalid entry entry for subtraction...Please retry!");
// flush scanner
scanner.next();
validAnswer = false;
}
} while (!validAnswer);
// Line break for code clarity
System.out.println();
// if else statement to determine if answer is correct
if (result == input) {
System.out.println("Well done, you guessed corectly!");
correctAnswer = true;
} else {
System.out.println("Sorry incorrect, Please attempt another subtraction");
correctAnswer = false;
}
} while (!correctAnswer);
}// end of subtract
/**
* A method that generates a random number between 1 and 10
* @return randomNumber (Returns random number between 1 and 10 inclusive)
*/
public static int generateRandomNumber() {
//setting up random
Random random = new Random();
// Declaring int for random number and defaulting to 0
int randomNumber = 0;
// Assigning randomNumber between 1 and 10
randomNumber = random.nextInt(10);
randomNumber++;
//Trace code, Remember to take out!
System.out.println("Trace: Random no is:" + randomNumber);
return randomNumber;
}// end of generateRandomNumber
/**
* Method that allows user to guess a random number between a set range. A
* message will then be displayed on screen to let them know if they were
* correct or not.
*/
public static void guessRandomNumber() {
// declare var for user guess and default to zero
int userGuess = 0;
// declare boolean relating to if number is valid
boolean validNumber = false;
// declare boolean relating to if guess is correct
boolean correctGuess = false;
// declaring int equal to return value from generateRandomNumber();
int secretNumber = generateRandomNumber();
//Do while loop that runs until user guesses correctly
do {
//Do while loop that runs until a valid entry is given (i.e. int)
do {
try {
//do while loop ensuring that user guess is between 1 and 10
do {
// Get user guess (between 1 and 10)
System.out.println("Please enter a number between 1 and 10...");
userGuess = scanner.nextInt();
if (userGuess < 1 || userGuess > 10) {
validNumber = false;
System.out.println("Please Ensure number is between 1 and 10");
}else {
validNumber=true;
}
} while (!validNumber);
} catch (Exception ex) {
//Print error message
System.out.println("Sorry invalid entry...");
// Flush scanner
scanner.next();
validNumber = false;
}
} while (!validNumber);
//If else statement that outputs a message informing user if guess correct
if (userGuess == secretNumber) {
System.out.println("Guess correct, well done!");
correctGuess = true;
} else {
System.out.println("Sorry guess Incorrect please try again!");
correctGuess = false;
}
} while (!correctGuess);
}// end ofGuessRandomNumber
/**
* Method that allows user to enter a string they want and print it a
* certain no of times
*/
public static void printLoop() {
// Declaring and initialising Variables
int noOfTimes = 0;
String print = null;
try {
System.out.println("Please enter what you would like to print");
print = scanner.next();
} catch (Exception ex) {
//error message
System.out.println("Please give a Valid Entry...");
// flush scanner
scanner.next();
}
System.out.println("Please enter how many times you wish to print...");
noOfTimes = scanner.nextInt();
for (int counter = 0; counter < noOfTimes; counter++) {
System.out.println(print);
}
}// End of printLoop
}// End of class
您可以使用mentod作为菜单并使用它来循环每个输入。 – Senthil 2011-04-13 02:00:06
如果您将座位订购代码放在单独的方法中，您可能会更容易想象，因此，如果您键入1，则大循环会调用方法。 – MeBigFatGuy 2011-04-13 02:01:19
嗅到家庭作业（我知道，因为几年后我做了同样的事情返回） – 2011-04-13 02:02:08