public void FindFirstCommonAncestorTest_InvalidCases()
{
// Arrange
var root = new BinaryTreeNode <int>(20);
var node1 = new BinaryTreeNode <int>(10);
var node2 = new BinaryTreeNode <int>(30);
var node3 = new BinaryTreeNode <int>(5);
var node4 = new BinaryTreeNode <int>(15);
var node5 = new BinaryTreeNode <int>(3);
var node6 = new BinaryTreeNode <int>(7);
var node7 = new BinaryTreeNode <int>(17);
root.Left = node1;
root.Right = node2;
node1.Left = node3;
node1.Right = node4;
node3.Left = node5;
node3.Right = node6;
node4.Right = node7;
TestHelper.PrintBinaryTree(root);
// Act
var result1 = Question_4_8.FindFirstCommonAncestor(root, node1, null);
var result2 = Question_4_8.FindFirstCommonAncestor(root, null, node2);
var result3 = Question_4_8.FindFirstCommonAncestor(null, node1, node2);
var result4 = Question_4_8.FindFirstCommonAncestor(root, node1, new BinaryTreeNode <int>(0));
// Assert
Assert.IsNull(result1, "Test 1 failed.");
Assert.IsNull(result2, "Test 2 failed.");
Assert.IsNull(result3, "Test 3 failed.");
Assert.IsNull(result4, "Test 4 failed.");
}
public void FindFirstCommonAncestorTest()
{
// Arrange
var root = new BinaryTreeNode <int>(20);
var node10 = new BinaryTreeNode <int>(10);
var node30 = new BinaryTreeNode <int>(30);
var node5 = new BinaryTreeNode <int>(5);
var node15 = new BinaryTreeNode <int>(15);
var node3 = new BinaryTreeNode <int>(3);
var node7 = new BinaryTreeNode <int>(7);
var node17 = new BinaryTreeNode <int>(17);
root.Left = node10;
root.Right = node30;
node10.Left = node5;
node10.Right = node15;
node5.Left = node3;
node5.Right = node7;
node15.Right = node17;
TestHelper.PrintBinaryTree(root);
// Act
var result10 = Question_4_8.FindFirstCommonAncestor(root, node10, node10);
var result10_2 = Question_4_8.FindFirstCommonAncestor(root, node5, node17);
var result10_3 = Question_4_8.FindFirstCommonAncestor(root, node3, node17);
var resultRoot = Question_4_8.FindFirstCommonAncestor(root, node10, node30);
var resultRoot2 = Question_4_8.FindFirstCommonAncestor(root, root, node5);
var resultRoot3 = Question_4_8.FindFirstCommonAncestor(root, node7, node30);
var result5 = Question_4_8.FindFirstCommonAncestor(root, node3, node7);
// Assert
Assert.AreEqual(node10, result10, "Incorrect first common ancestor found for nodes 10 and 10.");
Assert.AreEqual(node10, result10_2, "Incorrect first common ancestor found for nodes 5 and 17.");
Assert.AreEqual(node10, result10_3, "Incorrect first common ancestor found for nodes 3 and 17.");
Assert.AreEqual(root, resultRoot, "Incorrect first common ancestor found for nodes 10 and 30.");
Assert.AreEqual(root, resultRoot2, "Incorrect first common ancestor found for nodes 20 and 5.");
Assert.AreEqual(root, resultRoot3, "Incorrect first common ancestor found for nodes 7 and 30.");
Assert.AreEqual(node5, result5, "Incorrect first common ancestor found for nodes 3 and 7.");
}