/// <summary>
/// This helper method will randomize the dictionary created in the last
/// method call, and decrease it's size to that specified by dictionarySize
/// from the last method call.
/// </summary>
/// <param name="dictionary">The dictionary to randomize.</param>
/// <param name="size">The size of the dictionary specified by the user.</param>
/// <returns>The user specified RedBlack Tree dictionary.</returns>
private RedBlack RandomizeDictionary( RedBlack dictionary, ref int size )
{
RedBlack returnValue = new RedBlack(),
nextWord = null;
tempTree = new RedBlack();
tempTree.DeepCopy( dictionary, ref tempTree );
Random random = new Random();
for( int dictionSize = 0; dictionSize < size; dictionSize++ )
{
/* Next random first character in a word to select for insertion.
* Randomly select a lower case alphabet letter from (97)'a' to (122)'z'.
*/
char firstChar = (char)random.Next( 97, 123 );
nextWord = NextWord( dictionary, firstChar );
string word = new string( (char[])nextWord.Key );
if( nextWord == Sentinel.Node )
{
dictionSize = dictionSize - 1;
usedWords[firstChar] = 0;
int actualSize = 0;
dictionary.GetActualSize( dictionary, ref actualSize );
if( actualSize == 0 && dictionSize == size - 1 )
{
size = dictionSize;
return returnValue;
}
else if( actualSize == 0 && dictionSize != size - 1 )
dictionary = tempTree;
}
else
{
dictionary.RB_Delete( ref dictionary, word.ToCharArray() );
returnValue.RB_Insert( ref returnValue, word.ToCharArray() );
}
nextWord = null;
}
return returnValue;
}
/// <summary>
/// This test will perform 100000 nodal element RB_Insert() operations and then
/// attempt to call RB_Delete() on all 100000 elements leaving only the Sentinel.Node
/// left in the test root RedBlack Tree and the same thing done on a second RedBlack
/// Binary Search Tree.
/// </summary>
public void Test13()
{
root = new RedBlack();
RedBlack test2 = new RedBlack();
for(int y = 0; y < 2; y++ )
{
for( int x = 0; x < 100000; x++ )
{
char [] next = Convert.ToString( x ).ToCharArray();
if( y == 0 )
root.RB_Insert( ref root, next );
else
test2.RB_Insert( ref test2, next );
}
for( int x = 99999; x > -1; x-- )
{
char [] next = Convert.ToString( x ).ToCharArray();
counter = counter + 1;
if( y == 0 )
root.RB_Delete( ref root, next );
else
test2.RB_Delete( ref test2, next );
}
Assert.IsTrue( root == Sentinel.Node || test2 == Sentinel.Node );
}
root.Inorder_Tree_Walk( root );
test2.Inorder_Tree_Walk( test2 );
}