public void Empty()
{
LinkedListToy <int> list = new LinkedListToy <int>();
C02Q01.RemoveDupes(list);
Assert.Null(list.Head);
}
public void CtorParams()
{
LinkedListToy <string> L = new LinkedListToy <string>("apple", "banana");
Assert.Equal("apple", L.Head.Data);
Assert.Equal("banana", L.Head.Next.Data);
Assert.Equal(null, L.Head.Next.Next);
}
public void TwoElements()
{
LinkedListToy <int> list = new LinkedListToy <int>(7, 7);
C02Q01.RemoveDupes(list);
Assert.NotNull(list.Head);
Assert.Equal(7, list.Head.Data);
Assert.Null(list.Head.Next);
}
public void SingleElement()
{
LinkedListToy <int> list = new LinkedListToy <int>(1);
C02Q01.RemoveDupes(list);
Assert.NotNull(list.Head);
Assert.Equal(1, list.Head.Data);
Assert.Null(list.Head.Next);
}
public void NoDupes()
{
LinkedListToy <int> list = new LinkedListToy <int>(7, 8, 9);
C02Q01.RemoveDupes(list);
Assert.NotNull(list.Head);
Assert.Equal(7, list.Head.Data);
Assert.Equal(8, list.Head.Next.Data);
Assert.Equal(9, list.Head.Next.Next.Data);
Assert.Null(list.Head.Next.Next.Next);
}
public void BasicLL()
{
LinkedListToy <string> L = new LinkedListToy <string>();
Assert.Equal(null, L.Head);
L.Append("apple");
L.Append("banana");
Assert.Equal("apple", L.Head.Data);
Assert.Equal("banana", L.Head.Next.Data);
Assert.Equal(null, L.Head.Next.Next);
}
public void ShortTest()
{
LinkedListToy <int> list = new LinkedListToy <int>(1, 2, 2, 3, 1);
C02Q01.RemoveDupes(list);
var node = list.Head;
int[] expectedOutcome = { 1, 2, 3 };
foreach (int i in expectedOutcome)
{
Assert.Equal(i, node.Data);
node = node.Next;
}
Assert.Null(node);
}
public static void RemoveDupes(LinkedListToy <int> list)
{
HashSet <int> seen = new HashSet <int>();
Node <int> prev = null;
Node <int> curr = list.Head;
while (curr != null)
{
if (!seen.Contains(curr.Data))
{
seen.Add(curr.Data);
prev = curr;
}
else
{
// prev cannot be list.Head
prev.Next = curr.Next;
}
curr = curr.Next;
}
}
