Book Image

Hands-On Data Structures and Algorithms with Python - Third Edition

By : Dr. Basant Agarwal
Book Image

Hands-On Data Structures and Algorithms with Python - Third Edition

By: Dr. Basant Agarwal

Overview of this book

Choosing the right data structure is pivotal to optimizing the performance and scalability of applications. This new edition of Hands-On Data Structures and Algorithms with Python will expand your understanding of key structures, including stacks, queues, and lists, and also show you how to apply priority queues and heaps in applications. You’ll learn how to analyze and compare Python algorithms, and understand which algorithms should be used for a problem based on running time and computational complexity. You will also become confident organizing your code in a manageable, consistent, and scalable way, which will boost your productivity as a Python developer. By the end of this Python book, you’ll be able to manipulate the most important data structures and algorithms to more efficiently store, organize, and access data in your applications.
Table of Contents (17 chapters)
14
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15
Index

Chapter 2: Introduction to Algorithm Design

Question 1

Find the time complexity of the following Python snippets:

  1. i=1 
    while(i<n): 
        i*=2 
        print("data")
    
  2. i =n
    while(i>0):
        print("complexity")
        i/ = 2
    
  3. for i in range(1,n):
        j = i 
        while(j<n):
            j*=2
    
  4. i=1
    while(i<n): 
        print("python")
        i = i**2
    

Solution

  1. The complexity will be O(log(n)).

    As we are multiplying the integer i by 2 in each step there will be exactly log(n) steps. (1, 2, 4, …… till n).

  1. The complexity will be O(log(n)).

    As we are dividing the integer i by 2 in each step there will be exactly log(n) steps. (n, n/2, n/4, …… till 1).

  1. The outer loop will run n times for each i in the outer loop, while the inner while loop will run log(i) times because we are multiplying...