1. Presented By: Mahmoud Rafeek Alfarra
MINISTRY OF EDUCATION & HIGHER EDUCATION
COLLEGE OF SCIENCE AND TECHNOLOGY
KHANYOUNIS- PALESTINE
Data structure
Using C#
Information Technology , 3’rd Semester
Lecture 12:
Operations of Queue
Presented By: Mahmoud Rafeek Alfarra

2. Outline Implementing the enqueue Implementing the dequeue
Implementing the Peek
Implementing the Clear
Implementing the Printall
Emank X Mezank !!

3. Implementing the enqueue operation
New nodes should be inserted at the front of the list, so that they become the top of the stack. 2
New item
Front
Rear
Ahmed 1
Ali
Mohamed
Ghadeer
Mohamed
Ghadeer
Ali
Front
Rear
Ahmed
Presented & Prepared by: Mahmoud R. Alfarra

4. Pseudo code of the enqueue operation
Create new object
If rear points to null
rear= NewItem
Front = NewItem
NewItem.next = null
Else
NewItem.next = rear
size++
index++
Presented & Prepared by: Mahmoud R. Alfarra

5. Implementing the dequeue operation
The removed element should be removed from the front of the list.
Front
Rear 1
Ali
Mohamed
Ghadeer
Mohamed
Ghadeer
Ali
Front
Rear
Ahmed
Presented & Prepared by: Mahmoud R. Alfarra

6. Pseudo code of the DeQueue operation
If front points to null
print (the queue is empty)
Else
for (current = Rear, current.next != Front, current = current.next);
Front = current;
index--;
size--;
Presented & Prepared by: Mahmoud R. Alfarra

7. Implementing the Peek operation
The retrieved element should be element of the Front of the list.
Front.name
Front.ID
Front.data…
Presented & Prepared by: Mahmoud R. Alfarra

8. Pseudo code of the Peek operation
If Front points to null
print (the queue is empty)
Else
return top
Presented & Prepared by: Mahmoud R. Alfarra

9. Implementing the Clear operation
The clearing of Queue means removing all the elements by set the Front and Rear point to null. 2 1
Front
Rear X X 2 1
Ali
Mohamed
Ghadeer
Presented & Prepared by: Mahmoud R. Alfarra

10. Pseudo code of the clear operation
If Front points to null
print (the stack is empty)
Else
Rear = null;
Front = null;
index = -1;
size = 0;
Presented & Prepared by: Mahmoud R. Alfarra

11. Implementing the Printall operation
The Print of all elements' data of the Queue means that we have to create a new pointer points every time to the next element.
current
Mohamed
Ghadeer
Ali
Front
Rear
Ahmed 4 3 2 1
Depending on your understanding of the Dequeue operation, write the pseudo code and method of the PrintAll operation
HW 11.1
Presented & Prepared by: Mahmoud R. Alfarra

12. Sorting and Finding elements
Depending on your understanding of the printAll() operation, write a find method which search about a specific data.
HW 12.2
Depending on your understanding of the printAll() operation, write a sort method which sorts the elements of the queue based on the name field.
HW 12.3
Presented & Prepared by: Mahmoud R. Alfarra

13. Emank X Mezank !!
مجالس الصالحين ...
ترفع الإيمان

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