Eye Spy

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Eye Spy

• Episode Three
• Cracking the Code

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cipher.txt
You should be able to do this. Open a ciphertext
file and display it like you did in NadaJava.
You dont need this I have it here for
demo purposes only.
test.txt
3
Deciphering

• Pass the entire String object that contains the
  ciphertext to your binary tree object.
• Your method should take a string as a parameter
  and return a string object.
• Put this string in your JTextArea designated for
  plaintext.
• If all went well, you should be able to read it!

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K.I.S.S.

• I start with an empty plaintext string.
• I set walk to root.
• A nice little for-loop the length of the string
  works.
• I love switch statements.
• if the character is ., walk goes left.
• if the character is -, walk goes right
• if its a blank, then
• get the letter from this node
• append it to your plaintext string
• set walk back to root so we can start from the
  top again with the next letter

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Enciphering
You should be able to do this. Open a ciphertext
file and display it like you did in NadaJava.
You dont need this I have it here for
demo purposes only.
7
Enciphering

• You should be able to use a for-loop the length
  of the plaintext string, tear off one char at a
  time and search for that node on the tree using a
  preorder traversal strategy.
• My preorder traversal method is called locate.

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Locate

• I pass in a node (first call passes root), and a
  string (convert the char on the string to a
  string so you can use the equals method or else
  be like MacDonalds and do it your own way.)
• I return a node object.

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Base Case

• If you get a null node, return null.
• If you get a node that has an alpha field that
  matches the one you want, return that node.
• Otherwise, set a new node, say, x to locate of
  the left node of the one passed in.
• If its not null, we must have found it, so
  return x.
• Otherwise, return locate of the right node of
  the one passed in.

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