public long extensionCount(char[] cs, int start, int end) {
   Strings.checkArgsStartEnd(cs, start, end);
   return mRootNode.contextCount(cs, start, end);
 }
 /**
  * Returns the sum of the counts of all character sequences one character longer than the
  * specified character sequence.
  *
  * @param cSeq Character sequence.
  * @return The sum of the counts of all character sequences one character longer than the
  *     specified character sequence.
  */
 public long extensionCount(CharSequence cSeq) {
   return mRootNode.contextCount(com.aliasi.util.Arrays.toArray(cSeq), 0, cSeq.length());
 }