Lecture_1_Introduction to Data Structures and Algorithm.pptx
- 1. Sana Yaqoob sanasundas618@GMAIL.C OM Lecture 1 DATA STRUC TURE S AND ALGORITHMS
- 2. COURSE OBJECTIVE The main objective of the course is to teach the students how to select and design data structures and algorithms that are appropriate for real world problem solving. Developing basic algorithms for manipulating stacks, queues, linked lists, trees, graphs. Developing the data structures (abstract data types) for implementing the aforementioned algorithms. Developing recursive algorithms for application in trees and graphs. This course is also about showing the correctness of algorithms and studying their computational complexities.
- 3. COURSE OUTCOMES On the successful completion of students are expected to: Understand the principle behind the course, the use of Abstract Data Types (ADT) Learn the commonly used ADT’s and their implementation Learn basic algorithms and basic methods used in design of algorithms Learn to compute the cost and benefits of different data structures and algorithms and how to select algorithms and data structures for a particular problem.
- 4. COURSE INFORMATION Textbooks ⚫ Data Structures Using C and C++ by Y. Langsam, M. J . Augenstein, A. M. Tenenbaum ⚫ Introduction to Data Structures in C by Ashok N. Kamthane ⚫ Data Structures and Algorithms by A. V. Aho, J . E. Hopcroft, J . D. Ullman ⚫ Algorithms in C++ by Robert Sedgewick
- 5. COURSE OUTLINE Introduction to Data Structure Algorithms Recursion Stacks Queues Lists and linked lists Trees Sorting Searching Graphs Hashing
- 6. GRADING Theory ⚫ Quizzes ---------------10% ⚫ Project/Assignments/Presentations ---------20% ⚫ Mid Term-------------- 20% ⚫ Final-------------------- 50% Lab ⚫ Quizzes ---------------10% ⚫ Lab journals/Assessments-----40% ⚫ Mid Term-------------- 20% ⚫ Final-------------------- 30%
- 7. INTRODUCTION TO DATA ST RUC T URE AND ABSTRACT DATA TYPES Week 1
- 8. WHAT IS DATA STRUCTURE? Data structure is a representation of data and the operations allowed on that data. • A data structure is a way to store and organize data in order to facilitate the access and modifications. • Data Structure are the method of representing of logical relationships between individual data elements related to the solution of a given problem.
- 9. BASIC DATA STRUCTURE Basic Data Structures Linear Data Structures Non-Linear Data Structures Arrays Linked Lists Stacks Queues Trees Graphs Hash Tables
- 11. SELECTION OF DATA STRUCTURE The choice of particular data model depends on two consideration: ⚫ It must be rich enough in structure to represent the relationship between data elements ⚫ The structure should be simple enough that one can effectively process the data when necessary
- 12. TYPES OF DATA STRUCTURE Linear: In Linear data structure, values are arrange in linear fashion. ⚫ Array: Fixed-size ⚫ Linked-list: Variable-size ⚫ Stack: Add to top and remove from top ⚫ Queue: Add to back and remove from front ⚫ Priority queue: Add anywhere, remove the highest priority
- 13. TYPES OF DATA STRUCTURE Non-Linear: The data values in this structure are not arranged in order. ⚫ Hash tables: Unordered lists which use a ‘hash function’ to insert and search ⚫ Tree: Data is organized in branches. ⚫ Graph: A more general branching structure, with less strict connection conditions than for a tree
- 14. TYPE OF DATA STRUCTURES Homogenous: In this type of data structures, values of the same types of data are stored. ⚫ Array Non-Homogenous: In this type of data structures, data values of different types are grouped and stored. ⚫ Structures ⚫ Classes
- 15. ABSTRACT DATA TYPE AND DATA STRUCTURE Definition:- ⚫ Abstract Data Types (ADTs) store data and allow various operations on the data to access and change it. ⚫ An ADT is a collection of data and associated operations for manipulating that data. Data Structures ⚫ Physical implementation of an ADT ⚫ data structures used in implementations are provided in a language (primitive or built-in) or are built from the language constructs (user-defined) ⚫ Each operation associated with theADT is implemented by one or more subroutines in the implementation
- 16. ABSTRACT DATA TYPE ADTs support abstraction, encapsulation, and information hiding. Abstraction is the structuring of a problem into well-defined entities by defining their data and operations. The principle of hiding the used data structure and to only provide a well-defined interface is known as encapsulation.
- 17. THE CORE OPERATIONS OF ADT Every Collection ADT should provide a way to: ⚫ add an item ⚫ remove an item ⚫ find, retrieve, or access an item Many, many more possibilities ⚫ is the collection empty ⚫ make the collection empty ⚫ give me a sub set of the collection
- 18. No single data structure works well for all purposes, and so it is important to know the strengths and limitations of several of them IMPORTANT !!!
- 19. STACKS Collection with access only to the last element inserted Last in first out insert/push remove/pop top make empty Data4 Data3 Data2 Data1 T op
- 20. QU E U ES Collection with access only to the item that has been present the longest Last in last out or first in first out enqueue, dequeue, front priority queues and dequeue Data1 Data2 Data3 Data4 Front Back
- 21. LIST A Flexible structure, because can grow and shrink on demand. Elements can be: Inserted Accessed Deleted At any position last first
- 22. TREE A Tree is a collection of elements called nodes. One of the node is distinguished as a root, along with a relation (“parenthood”) that places a hierarchical structure on the nodes. Root