While Loops

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/**
* ---------------------------------------------------------------------------
* File name: WhileLoopExercises.java
* Project name: Winter Study Guide
* ---------------------------------------------------------------------------
* Author’s name and email: Michael Schneider, schneidm@etsu.edu
* Course-Section: All
* Creation Date: 1/5/15
* Last modified: Schneider 1/5/15 schneidm@etsu.edu
* ---------------------------------------------------------------------------
*/
import java.util.Scanner;

/**
* Class Name: WhileLoopExercises <br>
* Class Purpose: To give example exercises on using while loop to create repetitive code
* <br>
*
* <hr>
* Date created: 1/5/15 <br>
* Last modified: Schneider 1/5/15 schneidm@etsu.edu
* @author Michael Schneider
*/
public class WhileLoopExercises{

	public static void main(String[] args){
	
		/*******************************************************
		*
		*	Examples
		*
		********************************************************/
		
		//Create a while loop that displays 0 to 15 to the screen


		int counter = 0;//Set initial state

		
		while(counter <= 15)//Conditional statement

		{
			System.out.println(" " + counter);
			counter++;//Update counter

		}
		
		
		//Using a while loop, displays ("That number isn't 4!") until the user enters 4

		
		Scanner kb = new Scanner(System.in);
		
		System.out.println("Enter the # 4");
		int input = kb.nextInt();//Initial State

		
		while(input != 4)//Conditional Statement

		{
			System.out.println("That number isn't 4!");
			input = kb.nextInt();//Update state

		}
		
		/**********************************
		*
		*  Counting Exercises
		*
		***********************************/
		
		//Problem 1

		//Create a while loop that counts from 1 to 10



		//Problem 2

		//Create a while loop that counts from 0 to 50 by counting by 5


		
		
		//Problem 3

		//Create a while loop that counts from 10 to 1



		
		
		/**********************************
		*
		*  Repetitive Exercises
		*
		***********************************/
		
		//Problem 1

		//Sum all the numbers from 1 to 50

		

		
		//Problem 2

		//  Write the necessary code to do the following:

		//		-Display the following menu to the user.  

		//    		1. Say "Hello"

		//    		2. Say "Good Bye"

		//	  		3. Exit

		//

		//		-Process the user's response

		//

		//		-Display an error message if the user enters an invalid number

		//			(i.e. a number not 1-3)

		//

		//		-Keep asking the user for input until they enter 3

		// 

		
		
	}

}
/**
* ---------------------------------------------------------------------------
* File name: WhileLoopAnswers.java
* Project name: Winter Study Guide
* ---------------------------------------------------------------------------
* Author’s name and email: Michael Schneider, schneidm@etsu.edu
* Course-Section: All
* Creation Date: 1/5/15
* Last modified: Schneider 1/5/15 schneidm@etsu.edu
* ---------------------------------------------------------------------------
*/
import java.util.Scanner;

/**
* Class Name: WhileLoopAnswers <br>
* Class Purpose: To give answers for the while loop exercises
* <br>
*
* <hr>
* Date created: 1/5/15 <br>
* Last modified: Schneider 1/5/15 schneidm@etsu.edu
* @author Michael Schneider
*/
public class WhileLoopAnswers{

	public static void main(String[] args){
	
		/*******************************************************
		*
		*	Examples
		*
		********************************************************/
		
		//Create a while loop that displays 0 to 15 to the screen


		int counter = 0;//Set initial state

		
		while(counter <= 15)//Conditional statement

		{
			System.out.println(" " + counter);
			counter++;//Update counter

		}
		
		
		//Using a while loop, displays ("That number isn't 4!") until the user enters 4

		
		Scanner kb = new Scanner(System.in);
		
		System.out.println("Enter the # 4");
		int input = kb.nextInt();//Initial State

		
		while(input != 4)//Conditional Statement

		{
			System.out.println("That number isn't 4!");
			input = kb.nextInt();//Update state

		}
		
		/**********************************
		*
		*  Counting Exercises
		*
		***********************************/
		
		//Problem 1

		//Create a while loop that counts from 1 to 10

		counter = 1;
		
		while(counter < 11)
		{
			System.out.print(" " + counter);
			counter++;
		}
		

		//Problem 2

		//Create a while loop that counts from 0 to 50 by counting by 5

		counter = 0;
		
		while(counter < 51)
		{
			System.out.print(" " + counter);
			counter+=5;
		}
		
		
		//Problem 3

		//Create a while loop that counts from 10 to 1


		counter = 10;
		
		while(counter > 0)
		{
			System.out.print(" " + counter);
			counter--;
		}
		
		
		
		/**********************************
		*
		*  Repetitive Exercises
		*
		***********************************/
		
		//Problem 1

		//Sum all the numbers from 1 to 50

		
		int sum = 0;
		counter = 1;
		
		while(counter < 51)
		{
			sum+=counter;
			counter++;
		}
		System.out.println("The total sum of 1 to 50 is: " + sum);
		
		//Problem 2

		//  Write the necessary code to do the following:

		//		-Display the following menu to the user.  

		//    		1. Say "Hello"

		//    		2. Say "Good Bye"

		//	  		3. Exit

		//

		//		-Process the user's response

		//

		//		-Display an error message if the user enters an invalid number

		//			(i.e. a number not 1-3)

		//

		//		-Keep asking the user for input until they enter 3

		// 

		
		System.out.println("Please choose an option from the menu below:"+
							"\n 1. Say \"Hello\" "+
							"\n 2. Say \"Good Bye \"" +
							"\n 3. Exit");
							
		int menuChoice = kb.nextInt();

		while(menuChoice != 3)
		{
			switch(menuChoice)
			{
				case 1:
					System.out.println("Hello!");
					break;
					
				case 2:
					System.out.println("Good Bye");
					break;
					
				default:
					System.out.println("Error... invalid input...");
			}
			
			System.out.println("Please choose an option from the menu below:"+
					"\n 1. Say \"Hello\" "+
					"\n 2. Say \"Good Bye \"" +
					"\n 3. Exit");
							
			menuChoice = kb.nextInt();
			
		}
		
		System.out.println("You have exited the menu!");
	}

}