public void TestTrieInsert()
{
// create root node.
TrieNode root = new TrieNode();
// insert the strings as dictionary
TrieOperation operation = new TrieOperation();
operation.Insert(root, "abc");
operation.Insert(root, "abcd");
operation.Insert(root, "aa");
operation.Insert(root, "abbbaba");
// assert for search operation
Assert.IsTrue(operation.Search(root, "abc"));
Assert.IsTrue(operation.Search(root, "abcd"));
Assert.IsTrue(operation.Search(root, "abbbaba"));
Assert.IsFalse(operation.Search(root, "abb"));
// delete abc from Trie node
operation.Delete(root, "abcd");
// assert for search operation.
Assert.IsFalse(operation.Search(root, "abcd"));
Assert.IsTrue(operation.Search(root, "abc"));
Assert.IsTrue(operation.Search(root, "abbbaba"));
}