Simple Logic Error In Cipher-shifting Program?

Feb 8, 2015

I was tasked with creating a program that encrypts a line of text (for example, CANDY) by shifting the letters X amount of times. For example, if the user inputs the sentence CANDY and selects a shift of 5, the output would be: HFSID. I got this part working fine. The issue I am having is with the decryption part of the program.

This is simply the reverse of the above, as the user would enter the phrase HFSID, with a shift of 5, and the program would output: CANDY. It works fine, all except for one letter, being the "F" letter. With my code, when I enter the above word to be decrypted it outputs: C[NDY

Obviously, that [ bracket is not an 'A'. I realise the issue falls with the equation, Here is my code:

public class SimpleEncryption {

/**
* @param args the command line arguments
*/
static int answer;
public static void main(String[] args) {
String cipher = JOptionPane.showInputDialog(null, "Please enter a sentence or word that you wish to encode or decode. This program uses"
+ " a basic cipher shift.");

[code]....

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Make Simple Caesar Cipher That Takes In String As First Argument

Jan 21, 2014

I'm trying to make a simple Caesar cipher that takes in a String as the first argument and a integer shift as the second argument. Namely, there appears to be a problem with the loop and how I have declared the array - I want the converted characters to be put into a new array called newCharacterArray, converted back to a String and displayed in the command prompt window.

public class Caesar {
public static void main(String inString, int k) {
System.out.println("String: " + inString);
char inStringArray[] = inString.toCharArray();

[code]....

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at home.Members.addUser(Members.java:16)
at home.Main.main(Main.java:14)"

Here is the code! :

Main.java class
Java Code: import java.util.Scanner;
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[code]....

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Oct 31, 2014

int a=Integer.parseInt(jTextField1.getText());
String c = "";
String d="";
if (a>32) {
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[Code] ....

I've made this but when i enter a no. than the result comes like eg 9=001001 so i need to delete the zeroes before 1 ....

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Oct 31, 2014

int a=Integer.parseInt(jTextField1.getText());
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[Code] ....

I've made this but when i enter a no. than the result comes like eg 9=001001 so i need to delete the zeroes before 1.

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Jan 2, 2015

I'm trying to fix this logic error in my slot machine game where no matter what slot combo comes up, it says you have won $10 and proceeds to add that amount to the balance and subtract the bet amount to the balance, even though it is not a winning combo! I've been trying to solve that and when doing so, I commented out Slot1.randNum1 == 0, Slot2.randNum2 ==0, and Slot3.randNum3 ==0 and anything relating to see if that was the problem, and it seemed like it was, because after that, the logic error described above was gone, but in doing so, the loss/win counter didn't increment, nor did the program pick up on the winning combos. However, I do not know why commenting out anything relating to randNum ==0 would cause that.

Here is the code for the processing (as you can see, some parts are commented in attempt to fix the logic error, but right now the code below is for the logic error that keeps on telling that the user has won):

public void askData ()
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title ();
int betAmount;
while (true)
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try
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[code]....

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Sep 12, 2014

My code runs and populates an arraylist. However my break statement, while stopping the loop ends up being added to the arraylist. And I'm not sure how to fix this error.

public static void main(String args[]) throws Exception
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Mar 2, 2014

I've decided to go back to basics and start using pseudocode--but i want to see if my logic is correct.so here's the first program:each delegate to a certain conference must wear a tag showing their name and the organization they represent as shown below:

######################

#### Annual Conference #####

######################

##NAME: ##

######################

##ORGANIZATION: ##

######################

write a class called TagMaker that prints out tags. supply methods to (a) set the name (b) set the organization (c) print tag with the name and organization (d) clear the name and organization (e) print a blank tag. then write a TagTester class to test the TagMaker class. so this is the pseudo code (or logic) that i've come up with for the program:

TagMaker main class:

-Prompt user to enter in first and last name, as well as their organization.

-Read user input for the name and organization.

-Return user input.

-Write conference tag showing the person's information.

-Clear information.

-Print blank tag.

1. i assume i would have to import a few java libraries.

Java Code: java.util.Scanner mh_sh_highlight_all('java'); and Java Code: java.io.*; mh_sh_highlight_all('java');

2. afterwards i would declare the instance variables (private, i assume). static too? so for example: Java Code: private static string firstName mh_sh_highlight_all('java');

3. i'm not sure if this program requires a constructor...being that i'm supposed to clear the program at the end anyway.

4. i create a public class declaring my input variable. example: Java Code: String first = firstName.nextLine(); mh_sh_highlight_all('java');

5. so i then i have to create methods that get/set the user input.

getter/setter example:

Java Code:

public String getFirst(){
return first;
}
public void setFirst(){
this.first = new first;
} mh_sh_highlight_all('java');

6. to print out both tags, would i write most of the code as part of a loop and make an "if" statement where the user input is valid, it prints out a tag with information, and another "if" statement that would automatically clear the buffer?

7. last i would create a tester class that would primarily be responsible for the program's output.

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Oct 8, 2014

import javax.swing.JOptionPane;
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public static void main ( String args[] ) {
double n1 = Double.parseDouble(JOptionPane.showInputDialog(" Enter first number: "));
double n2 = Double.parseDouble(JOptionPane.showInputDialog(" Enter second number: "));
String x = JOptionPane.showInputDialog("Enter operator: ");
double result;

[code].....

Write a program that mimics a calculator. The program will need to accept as input two numeric double values, and accept the operation to be performed as the third input. The operation to be performed will be input in the form of the character representing the java operator for the operation to be performed (i.e + for addition, - for subtraction, * for multiplication, / for division, or % for modulus). Once the program has read these 3 inputs it should output the numbers, the operator, and the result. (For division, if the denominator is zero, the program will output an appropriate message (i.e division by zero is an invalid operation). Please use the JOptionPane class for both accepting the required inputs and for the required output demonstrated below.Some sample output may look as follows:

3 + 4 = 7
13 * 5 = 65
10 / 3 = 3.33333333

Error Messages:
3 errors found:
File: /Users/gcaruso/Documents/CISS 110/Module 3/Module 4/Calculator.java [line: 23]
Error: /Users/gcaruso/Documents/CISS 110/Module 3/Module 4/Calculator.java:23: 'else' without 'if'
File: /Users/gcaruso/Documents/CISS 110/Module 3/Module 4/Calculator.java [line: 31]
Error: /Users/gcaruso/Documents/CISS 110/Module 3/Module 4/Calculator.java:31: 'else' without 'if'
File: /Users/gcaruso/Documents/CISS 110/Module 3/Module 4/Calculator.java [line: 37]
Error: /Users/gcaruso/Documents/CISS 110/Module 3/Module 4/Calculator.java:37: 'else' without 'if

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Feb 24, 2014

So I have this 2D array that contains some Object foo.

[f] [f] [f][f]

[3][3][3][3]

[b][b][b][b]

[x][x][x][x]

[ ][ ][ ][ ]

[ ][ ][ ][ ]

[ ][ ][ ][ ]

I want to shift all the rows down one unit, starting for the rows containing x. So the x row is first shifted to row 4. then the b row shifted to where the x row was, row 3 and so on. My question is:

1. How can I check if the next row is empty

2. How do I shift a row down

Here's my attempt:

Java Code:

//board is the 2D array defined elsewhere
public void shiftRowDown(){
int counter = 0;
int rowCounter = 0;
for (int i = 0; i < this.board.length; i++) {

[code]....

Is this correct.

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Example: I am trying to get this phone number, 545-319-8712 to become 212-086-5489. The shift value is 3. So basically since the phone number given to me is 3 numbers higher than the phone number I am trying to get, so if the first number I receive from the user is higher than 2 then I would shift the number the user gave me down by the shift value I have already gotten.

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If I have to shift a number down 4 spots and I get the number 1 from the user than I want to get the number 1 to first down four times to become 7.

[1] -> 0 -> 9 -> 8 ->[7]

Basically if I have to shift a number down 4 and the number is less than or equal to 3 then I want it to continue from 9 .

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import java.util.Scanner;
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[Code] .....

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at java.awt.Container.add(Unknown Source)
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Here's a screenshot : 2014-09-13 at 7.39.23 PM.jpg

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The problem was that in the getNormal function, the input vector argument was a reference to the 'D' vector for the mirror in my 'objects' ArrayList so the .normalize() function acted upon the original vector, changing it's value and screwing things up. The two classes I talked about:

Optics: (note line 64. this line returns a null intersection when it shouldn't)

package ofer.davidson;
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ArrayList<Object> objects;
ArrayList<Ray> rays;
 
[Code] .....

Also why doesn't my background turn white??

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Aug 12, 2014

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2 11000.00 1000.00 12000.00
3 12000.00 1000.00 13000.00
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