public void ReturnKthToLastTest(int k, int expected)
{
var testList = new LinkedList(new int[] { 1, 2, 3, 2, 1, 4, 5, 6, 5, 4, 3, 2, 1, 10, 1 });
int result = Question_2_2.ReturnKthToLast(testList, k);
Assert.AreEqual(expected, result, $"{k}th element {expected} is expected but got {result}.");
result = Question_2_2.ReturnKthToLastRecursive(testList, k);
Assert.AreEqual(expected, result, $"{k}th element {expected} is expected but got {result} - recursive.");
result = Question_2_2.ReturnKthToLastOnePass(testList, k);
Assert.AreEqual(expected, result, $"{k}th element {expected} is expected but got {result} - one pass.");
}
public void ReturnKthToLastRecursiveTest_InvalidCases()
{
try
{
int k = 2;
Question_2_2.ReturnKthToLastRecursive(new LinkedList(new int[] { 1 }), k);
Assert.Fail($"ArgumentOutOfRangeException was not thrown for invalid k={k}.");
}
catch (ArgumentOutOfRangeException) { }
try
{
int k = -1;
Question_2_2.ReturnKthToLastRecursive(new LinkedList(new int[] { 1 }), k);
Assert.Fail($"ArgumentOutOfRangeException was not thrown for invalid k={k}.");
}
catch (ArgumentOutOfRangeException) { }
}
