public IEnumerable <double> BackEnumerator()
{
DoublyNode <Double> current = tail;
while (current != null)
{
yield return(current.Data);
current = current.Previous;
}
}
IEnumerator <double> IEnumerable <double> .GetEnumerator()
{
DoublyNode <Double> current = head;
while (current != null)
{
yield return(current.Data);
current = current.Next;
}
}
public double CalcSum()
{
DoublyNode <Double> current = head;
double sum = 0d;
while (current != null)
{
sum += Convert.ToDouble(current.Data);
current = current.Next;
}
return(sum);
}
public bool Contains(double data)
{
DoublyNode <Double> current = head;
while (current != null)
{
if (current.Data.Equals(data))
{
return(true);
}
current = current.Next;
}
return(false);
}
int count;//count elements in list
//add element
public void Add(double data)
{
DoublyNode <Double> node = new DoublyNode <Double>(data);
if (head == null)
{
head = node;
}
else
{
tail.Next = node;
node.Previous = tail;
}
tail = node;
count++;
}
public void AddFirst(double data)
{
DoublyNode <Double> node = new DoublyNode <Double>(data);
DoublyNode <Double> temp = head;
node.Next = temp;
head = node;
if (count == 0)
{
tail = head;
}
else
{
temp.Previous = node;
}
count++;
}
public DoublyNode <Double> FindMaxNode()
{
DoublyNode <Double> current = head;
DoublyNode <Double> max = current;
while (current != null)
{
//find last max
if (max.Data <= current.Data)
{
max = current;
}
current = current.Next;
}
return(max);
}
public void deleteElementsBeforeMax()
{
DoublyNode <Double> max = FindMaxNode();
DoublyNode <Double> current = head;
while (current != null)
{
if (current.Data != max.Data)
{
Remove(current.Data);
}
else
{
break;
}
current = current.Next;
}
}
public double CalcNumOfLessThanAvLetters()
{
DoublyNode <Double> current = head;
int counter = 0;
double data = 0d;
double sum = CalcSum();
while (current != null)
{
data = Convert.ToDouble(current.Data);
if (data.CompareTo(sum / Count) < 0)
{
counter++;
}
current = current.Next;
}
return(counter);
}
public bool Remove(double data)
{
DoublyNode <Double> current = head;
//to search deleting node
while (current != null)
{
if (current.Data.Equals(data))
{
break;
}
current = current.Next;
}
if (current != null)
{
//if node is not last
if (current.Next != null)
{
current.Next.Previous = current.Previous;
}
else
{
tail = current.Previous;
}
//if node is not first
if (current.Previous != null)
{
current.Previous.Next = current.Next;
}
else
{
head = current.Next;
}
count--;
return(true);
}
return(false);
}
public void Clear()
{
head = null;
tail = null;
count = 0;
}
