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WordScramblerQuestion.pdf

Starter Code

WordScrambler.java

public class WordScrambler 
{ 
  private String[] scrambledWords;  

  /** @param wordArr an array of String objects 
   *         Precondition: wordArr.length is even 
   */ 
  public WordScrambler(String[] wordArr) 
  {   
    scrambledWords = mixedWords(wordArr); 
  } 


  /** @param word1 a String of characters 
   *  @param word2 a String of characters 
   *  @return a String that contains the first half of word1 and the second half of word2 
   */  
  public String recombine(String word1, String word2) 
  {  /* to be implemented in part (a) */ 


  } 


  /** @param words an array of String objects 
   *         Precondition: words.length is even 
   *  @return an array of String objects created by recombining pairs of strings in array words 
   *  Postcondition: the length of the returned array is words.length 
   */ 
  public String[] mixedWords(String[] words) 
  {  /* to be implemented in part (b) */  

  } 

  // There may be instance variables, constructors, and methods that are not shown. 
} 

WordScramblerTester.java

import java.util.ArrayList;
public class WordScramblerTester
{

	public static void main(String[] args)
	{
		String[] words={"apple", "pear", "this", "cat"};
		WordScrambler w=new WordScrambler(words);
		System.out.println("Testing part (a):the recombine method" );
		System.out.println("Should be 'apar': "+w.recombine("apple","pear"));
		System.out.println("Should be 'peple': "+w.recombine("pear","apple"));

		System.out.println("Testing part (b): the mixedWords method" );
		System.out.println("Sould be 'apar', 'peple', 'that', 'cis':");
		String[] output=w.mixedWords(words);
		for (String s:output) System.out.print(s+" ");

	}


}

Solutions

part(a)

private String recombine(String word1, String word2)
{
  word1=word1.subString(0,(word1.length()/2)+1);
  word2=word2.subString(word2.length()/2,word2.length());
  String word3= word1.concat(word2);
  return word3;
}

or

public String recombine(String word1, String word2) 
  {  return word1.substring(0,word1.length()/2)+word2.substring(word2.length()/2);} 

part(b)

public String[] mixedWords(String[] words) 
  {  String charlie [] = new String[words.length];

  		for(int w = 0; w<=words.length-2; w+=2){
		  String buffer1 =words[w];
		  String buffer2 =words[w+1];

		  charlie[w]=recombine(buffer1,buffer2);
		  charlie[w+1]=recombine(buffer2,buffer1);

	  }
	  return charlie;
  }