Chapter 1

1. Design and Analysis
of Algorithms
S. Sridhar

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Chapter 1
Introduction to
Algorithms

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Chapter Objectives

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What is an algorithm?
• An algorithm is a set of instructions to solve a given problem.

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Some Examples of Algorithms in daily life

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A Typical Algorithm Environment

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Characteristics of an Algorithm

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Characteristics of an Algorithm

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Need for Efficiency
• Time
• Space

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Stages of Problem Solving
• Understanding the problem
• Planning an algorithm
• Designing an algorithm
• Validating and verifying an algorithm
• Analyzing an algorithm
• Implementing an algorithm
• Performing empirical analysis (if necessary)

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Computation Model
Need of Computation model

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Data Organization

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Algorithm Design

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Algorithm Specification
Communication to programmer is called algorithm
specification
1. Natural Language
2. Pseudocode
3. Programming language

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Validating and Verification

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Analysis of Algorithms

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Time and Space Complexity

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Comparison of Algorithms

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Empirical and Post martem Analysis

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Classification of Algorithms

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Recursive Algorithms

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Parallel and Distributed Algorithms

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Exact Vs Approximation Algorithms

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Deterministic Vs randomized Algorithms

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Based on Design
Example Greedy, dynamic programming, Brute force
Techniques.

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Based on Specialization
 General Algorithms
 Example; Searching and Sorting
 Domain Specific Algorithms
 String Algorithms
 Graph Algorithms

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Some Interesting Problems

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Based on Tractability

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Example of Tractability

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Glossary

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Glossary