CSC 2300 Data Structures

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CSC 2300Data Structures Algorithms

• February 2, 2007
• Chapter 3. Lists, Stacks, and Queues

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What You Should Already Know
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Today Linear Structures
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Abstract Data Types (ADT)
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Linear Structures Operations
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Arrays and Vectors
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Linked Lists
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A Linked List
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Deletion from a Linked List
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Insertion into a Linked List
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Discussion

• In principle, if we know where a change is to be
  made, inserting or removing an item from a linked
  list does not require moving lots of items, and
  instead involves only a constant number of
  changes to node links.
• What are the special cases?
• Adding to the front or removing the first item
  requires a link to the front of the linked list.
• Adding at the end requires a link to the last
  node.
• What about removing the last item?
• We must find the next-to-last item.
• How to do so efficiently?

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A Doubly Linked List

• How to reduce coding work to handle the special
  cases?

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Header and Tail Nodes

• What if the list were empty?

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Insertion in Doubly Linked List
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Remove Node in Doubly Linked List

• p-gtprev-gtnext p-gtnext
• p-gtnext-gtprev p-gtprev
• delete p

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Erase Routines
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Standard Template Library (STL)
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STL vector
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STL list
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Stacks
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Stack Model

• Input to a stack is by push, output is by pop and
  top

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Stack Model

• Only the top element is accessible

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Queues
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Queue Model