public void AddToEmptyBalancedTreeShouldHaveSpecificProperties()
{
BalancedTree <int> tree = new BalancedTree <int>();
tree.Add(42);
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(1, tree.Size(), "Tree should have one node");
Assert.AreEqual(0, tree.Height(), "Tree should have height of 1");
Assert.AreEqual("42", tree.ToString(), "Tree should have comma separated list of values");
}
public void AddingSeveralValuesToBalancedTreeShouldMaintainBalance()
{
BalancedTree <int> tree = new BalancedTree <int>();
tree.Add(42);
// tree should now look like this:
// 42
tree.Add(17);
// tree should now look like this:
// 42
// /
// 17
tree.Add(0);
// tree should now look like this:
// 42
// / \
// 17 0
tree.Add(213401);
// tree should now look like this:
// 42
// / \
// 17 0
// /
// 213401
tree.Add(-1);
// tree should now look like this:
// 42
// / \
// 17 0
// / /
// 213401 -1
tree.Add(9);
// tree should now look like this:
// 42
// / \
// 17 0
// / \ /
// 213401 9 -1
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(6, tree.Size(), "Tree should have six nodes");
Assert.AreEqual(2, tree.Height(), "Tree should have height of 2");
Assert.AreEqual("42, 17, 213401, 9, 0, -1", tree.ToString(), "Tree should have comma separated list of values");
// adding one more should add the node to the "0" on the right
tree.Add(-69);
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(7, tree.Size(), "Tree should have seven nodes");
Assert.AreEqual(2, tree.Height(), "Tree should have height of 2");
Assert.AreEqual("42, 17, 213401, 9, 0, -1, -69", tree.ToString(), "Tree should have comma separated list of values");
}
public void RemovingAValueThatExistsShouldMaintainBalanceAndReturnTrue()
{
BalancedTree <int> tree = new BalancedTree <int>();
tree.Add(42);
// remove the root node - should return true and make the tree empty
Assert.IsTrue(tree.Remove(42), "Should be able to remove 42");
Assert.IsTrue(tree.IsEmpty, "Tree should be empty again");
tree.Add(42);
tree.Add(17);
tree.Add(0);
tree.Add(213401);
tree.Add(-1);
tree.Add(9);
// tree should now look like this:
// 42
// / \
// 17 0
// / \ /
// 213401 9 -1
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(6, tree.Size(), "Tree should have six nodes");
Assert.AreEqual(2, tree.Height(), "Tree should have height of 2");
Assert.AreEqual("42, 17, 213401, 9, 0, -1", tree.ToString(), "Tree should have comma separated list of values");
// simple case - remove a leaf
Assert.IsTrue(tree.Remove(-1), "Should have been able to remove 9");
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(5, tree.Size(), "Tree should have five nodes");
Assert.AreEqual(2, tree.Height(), "Tree should have height of 2");
Assert.AreEqual("42, 17, 213401, 9, 0", tree.ToString(), "Tree should have comma separated list of values");
// tree should now look like this:
// 42
// / \
// 17 0
// / \
// 213401 9
// remove 213401 - should move 9 to the left child of 17
Assert.IsTrue(tree.Remove(213401), "Should have been able to remove 213401");
// tree should now look like this:
// 42
// / \
// 17 0
// /
// 9
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(4, tree.Size(), "Tree should have four nodes");
Assert.AreEqual(2, tree.Height(), "Tree should have height of 2");
Assert.AreEqual("42, 17, 9, 0", tree.ToString(), "Tree should have comma separated list of values");
// add a few more nodes back into the tree and remove a node with two subtrees
tree.Add(-1);
tree.Add(69);
tree.Add(213401);
// tree should now look like this:
// 42
// / \
// 17 0
// / \ / \
// 9 69 -1 213401
Assert.IsTrue(tree.Remove(17), "Should have been able to remove 17");
// tree should now look like this:
// 42
// / \
// 69 0
// / / \
// 9 -1 213401
Assert.IsFalse(tree.IsEmpty, "Tree is not empty");
Assert.AreEqual(6, tree.Size(), "Tree should have six nodes");
Assert.AreEqual(2, tree.Height(), "Tree should have height of 2");
Assert.AreEqual("42, 69, 9, 0, -1, 213401", tree.ToString(), "Tree should have comma separated list of values");
}