public bool Contains(string word)
{
if (string.IsNullOrEmpty(word))
{
return false;
}
var nextNode = _root.Next(word[0]);
for (var i = 1; nextNode != null && i < word.Length; i++)
{
nextNode = nextNode.Next(word[i]);
}
return nextNode != null && nextNode.Eow;
}