public void Test_Find_For_Empty_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
// Act
Data data = bt.FindNode(7); // Should be no node to find...
// Assert
Assert.IsNull(data);
}
public void Test_Find_Succeeds_For_Single_Node_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
Data data = new Data();
bt.Insert(17, data);
// Act
data = bt.FindNode(17); // Should find the single node (17 == 17)...
// Assert
Assert.IsNotNull(data);
}
public void Test_Find_On_Non_Existant_Key_Fails_For_Single_Node_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
Data data = new Data();
bt.Insert(17, data);
// Act
data = bt.FindNode(23); // Should be no node to find (23 != 17)...
// Assert
Assert.IsNull(data);
}
public void Test_Find_Succeeds_When_Searching_A_Depth_Equals_2_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
BuildLeftUnbalancedTree(bt);
Data data = new Data(17, "Data4");
bt.Insert(17,data); // Tree (should have a depth of two, new leaf node.
// Act
data = bt.FindNode(17); // Should find the single node (17 == 17)...
// Assert
Assert.IsNotNull(data);
}
public void Test_Delete_On_Single_Node_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
Data data = new Data(17, "Data17");
bt.Insert(17, data);
// Act
bool removed = bt.Remove(17); // Should find the single node (17 == 17)...
// Assert
Assert.IsTrue(removed);
Assert.IsTrue(bt.TreeDepth() == 0);
}
private void BuildSevenNodeBalancedTree(BinaryTree bt)
{
// Building a 7-node tree. This as a node with only a left child, a node with only a right child,
// and nodes that have both left and right children. Tree that looks like this and has a depth of four:
// 4
// / \
// 3 9
// / / \
// 1 7 11
// \
// 15
int[] iKeys = { 4, 3, 9, 1, 7, 11, 15 };
string[] dataStrings = { "Data1", "Data2", "Data3", "Data4", "Data5", "Data6", "Data7" };
for (int i=0; i<7; i++)
{
Data data = new Data(iKeys[i], dataStrings[i]);
bt.Insert(iKeys[i], data);
}
}
private void BuildRightUnbalancedTree(BinaryTree bt)
{
int[] iKeys = { 4, 8, 16 };
string[] dataStrings = { "Data1", "Data2", "Data3" };
for (int i = 0; i < 7; i++)
{
Data data = new Data(iKeys[i], dataStrings[i]);
bt.Insert(iKeys[i], data);
}
}
public void Test_Tree_Depth_For_Single_Node_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
Data data = new Data();
b.Insert(1, data);
// Act
int depth = b.TreeDepth();
// Assert
Assert.IsTrue(depth == 1);
}
public void Test_Tree_Depth_For_Seven_Node_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
BuildSevenNodeBalancedTree(b);
// Act
int depth = b.TreeDepth();
// Assert
Assert.IsTrue(depth == 4);
}
public void Test_Tree_Depth_For_Null_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
// Act
int depth = b.TreeDepth();
// Assert
Assert.IsTrue(depth == 0);
}
public void Test_TreeIsBalanced2_For_Single_Node_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
Data data = new Data();
bt.Insert(5, data);
// Act
bool balanced = bt.TreeIsBalanced2();
// Assert
Assert.IsTrue(balanced);
}
public void Test_TreeIsBalanced1_Left_Unbalanced_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
BuildLeftUnbalancedTree(b);
// Act
bool balanced = b.TreeIsBalanced1();
// Assert
Assert.IsFalse(balanced);
}
public void Test_TreeIsBalanced1_For_Single_Node_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
Node tree = new Node();
// Act
bool balanced = b.TreeIsBalanced1();
// Assert
Assert.IsTrue(balanced);
}
public void Test_Remove_On_Root_Node_With_Left_and_right_Subtrees()
{
// Arrange
BinaryTree bt = new BinaryTree();
// The test tree looks like:
// 11
// / \
// 5 17
// / \
// 2 7
// / \
// 1 4
// /
// 3
Node[] nArray = new Node[8];
nArray[0] = new Node(11); // This is the node we will delete below (root node).
nArray[1] = new Node(5);
nArray[2] = new Node(17);
nArray[3] = new Node(2);
nArray[4] = new Node(7);
nArray[5] = new Node(1);
nArray[6] = new Node(4);
nArray[7] = new Node(3);
// This order of insertion should create a our "complex" tree.
for (int i = 0; i < 8; i++)
{
bt.Insert(nArray[i]);
}
// Act
bool removed = bt.Remove(11);
// Assert
Assert.IsTrue(removed);
Queue<Node> queue = bt.TreeToQueue(); // Get the remaining elements to validate them...
Assert.IsTrue(queue.Count == 7);
Assert.IsTrue(1 == queue.Dequeue().iKey);
Assert.IsTrue(2 == queue.Dequeue().iKey);
Assert.IsTrue(3 == queue.Dequeue().iKey);
Assert.IsTrue(4 == queue.Dequeue().iKey);
Assert.IsTrue(5 == queue.Dequeue().iKey);
Assert.IsTrue(7 == queue.Dequeue().iKey);
Assert.IsTrue(17 == queue.Dequeue().iKey);
}
public void Test_Remove_On_Null_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
// Act
bool removed = bt.Remove(23); // Shouldn't find any node match.
// Assert
Assert.IsFalse(removed);
}
public void Test_Remove_On_Node_With_Only_A_Right_Subtree()
{
// Arrange
BinaryTree bt = new BinaryTree();
Node n1 = new Node(17);
Node n2 = new Node(23); // This is the node we will delete.
Node n3 = new Node(29);
// This order of insertion should create a right-only subtree.
bt.Insert(n1);
bt.Insert(n2);
bt.Insert(n3);
// Act
bool removed = bt.Remove(23);
// Assert
Assert.IsTrue(removed);
Assert.IsTrue(bt.TreeDepth() == 2);
}
public void Test_Remove_On_Node_With_Only_A_Left_Subtree()
{
// Arrange
BinaryTree bt = new BinaryTree();
Node n1 = new Node(17);
Node n2 = new Node(14); // This is the one we will remove.
Node n3 = new Node(9);
// This order of insertion should create a left-only subtree.
bt.Insert(n1);
bt.Insert(n2);
bt.Insert(n3);
// Act
bool removed = bt.Remove(14);
// Assert
Assert.IsTrue(removed);
Assert.IsTrue(bt.TreeDepth() == 2);
Queue<Node> queue = bt.TreeToQueue();
Assert.IsTrue(queue.Dequeue() == n3);
Assert.IsTrue(queue.Dequeue() == n1);
}
public void Test_TreeIsBalanced1_Seven_Node_Balanced_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
BuildSevenNodeBalancedTree(b);
// Act
bool balanced = b.TreeIsBalanced1();
// Assert
Assert.IsTrue(balanced);
}
public void Test_TreeIsBalanced2_For_Null_Tree()
{
// Arrange
BinaryTree b = new BinaryTree();
// Act
bool balanced = b.TreeIsBalanced2();
// Assert
Assert.IsTrue(balanced);
}
public void Test_Find_Succeeds_When_Walking_Complex_Tree()
{
// Arrange
BinaryTree bt = new BinaryTree();
BuildSevenNodeBalancedTree(bt);
int iVal = 9; // Internal Node in tree...
// Act
Data data = bt.FindNode(iVal); // Should find the single node (17 == 17)...
// Assert
Assert.IsNotNull(data);
}
public void Test_Remove_On_Node_With_Left_and_right_Leaves()
{
// Arrange
BinaryTree bt = new BinaryTree();
Node n1 = new Node(17);
Node n2 = new Node(23); // This is the node we will delete.
Node n3 = new Node(21);
Node n4 = new Node(29);
bt.Insert(n1);
bt.Insert(n2); // Node to delete.
bt.Insert(n3);
bt.Insert(n4);
// Act
bool removed = bt.Remove(23);
// Assert
Assert.IsTrue(removed);
Queue<Node> queue = bt.TreeToQueue(); // To validate the remaining tree nodes.
Assert.IsTrue(queue.Count == 3);
Assert.IsTrue(17 == queue.Dequeue().iKey);
Assert.IsTrue(21 == queue.Dequeue().iKey);
Assert.IsTrue(29 == queue.Dequeue().iKey);
}