public void GivenZillowExampleWhenDeleteRootExpectMiddleReplacement()
{
// arrange
// 5
// / | \
// 4 5 9
// / /
// 2 7
// |
// 2
TrinaryTree startTree = this.GetBasicTree();
// create expected tree
// 5
// / \
// 4 9
// / /
// 2 7
// |
// 2
var expectedTree = new TrinaryTree(5);
expectedTree.RootNode.Left = new TrinaryTree.TrinaryTreeNode(4);
expectedTree.RootNode.Left.Left = new TrinaryTree.TrinaryTreeNode(2);
expectedTree.RootNode.Left.Left.Middle = new TrinaryTree.TrinaryTreeNode(2);
expectedTree.RootNode.Right = new TrinaryTree.TrinaryTreeNode(9);
expectedTree.RootNode.Right.Left = new TrinaryTree.TrinaryTreeNode(7);
// act
expectedTree.Delete(5);
// assert
}
public void GivenRightOnlyChildrenWhenDeleteExpectMinFromRightSubtreeAsReplacement2()
{
// arrange
// create start tree
// 5
// \
// 7 <-- to remove
// \
// 12
// / | \
// replacement --> 9 12 14
// \
// 10
var startTree = new TrinaryTree(5);
startTree.RootNode.Right = new TrinaryTree.TrinaryTreeNode(7);
startTree.RootNode.Right.Right = new TrinaryTree.TrinaryTreeNode(12);
startTree.RootNode.Right.Right.Left = new TrinaryTree.TrinaryTreeNode(9);
startTree.RootNode.Right.Right.Left.Right = new TrinaryTree.TrinaryTreeNode(10);
startTree.RootNode.Right.Right.Middle = new TrinaryTree.TrinaryTreeNode(12);
startTree.RootNode.Right.Right.Right = new TrinaryTree.TrinaryTreeNode(14);
// act
startTree.Delete(7);
// expected tree
// 5
// \
// 12
// / | \
// 9 12 14
// \
// 10
// assert
Assert.Equal(5, startTree.RootNode.Data);
startTree.RootNode.AssertLeftIsNull().AssertMiddleIsNull();
Assert.Equal(12, startTree.RootNode.Right.Data);
Assert.Equal(14, startTree.RootNode.Right.Right.Data);
AssertNoChildren(startTree.RootNode.Right.Right);
Assert.Equal(12, startTree.RootNode.Right.Middle.Data);
AssertNoChildren(startTree.RootNode.Right.Middle);
Assert.Equal(9, startTree.RootNode.Right.Left.Data);
startTree.RootNode.Right.Left.AssertLeftIsNull().AssertMiddleIsNull();
Assert.Equal(10, startTree.RootNode.Right.Left.Right.Data);
AssertNoChildren(startTree.RootNode.Right.Left.Right);
}
public void GivenEmptyTreeWhenDeleteExpectNoChange()
{
// arrange
var fixture = new Fixture();
var nonExistantValue = fixture.Create <int>();
var tree = new TrinaryTree();
// act
tree.Delete(nonExistantValue);
// assert
tree.RootNode.Should().BeNull();
}
public void GivenIdenticalNumbersWhenDeleteExpectLastOneRemoved()
{
// arrange
var fixture = new Fixture();
var valueToAdd = fixture.Create <int>();
var tree = new TrinaryTree(valueToAdd);
tree.RootNode.Middle = new TrinaryTree.TrinaryTreeNode(valueToAdd);
tree.RootNode.Middle.Middle = new TrinaryTree.TrinaryTreeNode(valueToAdd);
// act
tree.Delete(valueToAdd);
// assert
tree.RootNode.Data.Should().Be(valueToAdd);
tree.RootNode.AssertLeftIsNull().AssertRightIsNull();
tree.RootNode.Middle.Data.Should().Be(valueToAdd);
AssertNoChildren(tree.RootNode.Middle);
}
public void GivenLeftOnlyChildrenWhenDeleteExpectLeftReassignedToParent()
{
// arrange
// 5
// / | \
// 4 5 9
// / /
// 2 7
// |
// 2
TrinaryTree startTree = this.GetBasicTree();
// create expected tree
// 5
// / | \
// 2 5 9
// | /
// 2 7
var expectedTree = new TrinaryTree(5);
expectedTree.RootNode.Left = new TrinaryTree.TrinaryTreeNode(4);
expectedTree.RootNode.Left.Left = new TrinaryTree.TrinaryTreeNode(2);
expectedTree.RootNode.Left.Left.Middle = new TrinaryTree.TrinaryTreeNode(2);
expectedTree.RootNode.Middle = new TrinaryTree.TrinaryTreeNode(5);
expectedTree.RootNode.Right = new TrinaryTree.TrinaryTreeNode(9);
expectedTree.RootNode.Right.Left = new TrinaryTree.TrinaryTreeNode(7);
// act
startTree.Delete(4);
// assert
Assert.Equal(5, startTree.RootNode.Data);
Assert.Equal(2, startTree.RootNode.Left.Data);
Assert.Equal(2, startTree.RootNode.Left.Middle.Data);
Assert.Equal(5, startTree.RootNode.Middle.Data);
Assert.Equal(9, startTree.RootNode.Right.Data);
Assert.Equal(7, startTree.RootNode.Right.Left.Data);
}