@@ -0,0 +1,559 @@
+// http://codingbat.com/prob/p103593%0A%0Apublic String wordAppend(String%5B%5D strings) %7B%0A  StringBuilder result = new StringBuilder();%0A  Map%3CString, Integer%3E instancesOfWords = new HashMap%3CString, Integer%3E();%0A  for (String word : strings) %7B%0A    int instancesOfWordCount = (!instancesOfWords.containsKey(word)) ? 0 : instancesOfWords.get(word);%0A    instancesOfWords.put(word, instancesOfWordCount + 1);%0A    instancesOfWordCount = instancesOfWords.get(word);%0A    if (instancesOfWordCount %25 2 == 0) %7B%0A      result.append(word);%0A    %7D%0A  %7D%0A  return result.toString();%0A%7D%0A

Create wordAppend.java