Link list 1 in data stucture

1. CS250 - Data Structures and
Algorithm
BESE-2A/B
Lecture 03

2. •
•
•
•
•
Outline
Problem with arrays
Solution
Introduction to Linked List
Arrays vs. Linked List
Linked List Pros & Cons
9/14/2012 DSA - Fall 2012 - SEECS, NUST 2

3. Our Prime Concern
• Performance & Efficiency
– In terms of time ;
• faster the execution, better the algorithm
– In terms of space ;
• lesser the space, better the data structure
9/14/2012 DSA - Fall 2012 - SEECS, NUST 3

4. Pros
• Easier to use and access
• Faster access to the
elements
– Takes constant time
– Base + ( item_number *
number_of_bytes)
Cons
• Fixed size
• One block allocation
– Fails if enough contiguous
memory isn’t available
• Complex position based
insertion
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– Expensive to maintain
ordered data OR insertion at
beginning
DSA - Fall 2012 - SEECS, NUST 4
Arrays
Most common data structure to implement
collections or to store data

5. Arrays
• Solution
– Dynamic Memory Allocation
– Faster insertion and deletion of elements without
changing the existing items
• Linked List
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6. Linked List
• Linked structure is a collection of
nodes storing data and links to
other nodes
• Dynamic Memory Allocation
– Consequently, nodes can locate
anywhere in the memory and each
node can point to any other node
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7. Linked List
• Linked structure is a collection of nodes storing
data and link to other nodes
struct Node {
int data;
Node * next;
};
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8. Array vs. Linked List
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9. Linked List
Pros
• Dynamic allocation
– the size is not required to be
known in advance
• Flexibility
– insert at (or delete from) any
position in constant time
• No single allocation of
memory needed
Cons
• Complex to use and access
– relatively complex as
compared to arrays
• No constant time access to
the elements
9/14/2012 DSA - Fall 2012 - SEECS, NUST 9

10. Question?
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