/// <summary>
/// Returns but does not remove the key-value pair with minimum key
/// </summary>
/// <returns></returns>
public override (K, V) Min()
{
PositionalList <Item> .Position p = FindMin();
Item item = p.element();
return(item.key, item.value);
}
/// <summary>
/// Returns but does not remove the key-value pair in front of the Queue
/// </summary>
/// <returns></returns>
public override (K, V) Min()
{
if (IsEmpty())
{
throw new InvalidOperationException("The Priority Queue is empty");
}
PositionalList <Item> .Position p = data.First();
Item item = p.element();
return(item.key, item.value);
}
/// <summary>
/// Adds a new key-value pair
/// </summary>
/// <param name="key"></param>
/// <param name="value"></param>
public override void Add(K key, V value)
{
Item newest = new IPriorityQueue <K, V> .Item(key, value);
PositionalList <IPriorityQueue <K, V> .Item> .Position walk = data.Last();
while (walk != null && newest < walk.element())
{
walk = data.Before(walk);
}
if (walk == null)
{
data.AddFirst(newest);
}
else
{
data.AddAfter(walk, newest);
}
}
/// <summary>
/// Returns the position of the minimum key
/// </summary>
/// <returns></returns>
public PositionalList <Item> .Position FindMin()
{
if (IsEmpty())
{
throw new InvalidOperationException("The Priority Queue is empty");
}
PositionalList <Item> .Position small = data.First();
PositionalList <Item> .Position walk = data.After(small);
while (walk != null)
{
if (walk.element() < small.element())
{
small = walk;
}
walk = data.After(walk);
}
return(small);
}
