#### 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.
Preface
Free Chapter
Python Data Types and Structures
Introduction to Algorithm Design
Algorithm Design Techniques and Strategies
Stacks and Queues
Trees
Heaps and Priority Queues
Hash Tables
Graphs and Algorithms
Searching
Sorting
Selection Algorithms
String Matching Algorithms
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Index

# Greedy algorithms

Greedy algorithms often involve optimization and combinatorial problems. In greedy algorithms, the objective is to obtain the optimum solution from many possible solutions in each step. We try to get the local optimum solution, which may eventually lead us to obtain the global optimum solution. The greedy strategy does not always produce the optimal solution. However, the sequence of locally optimal solutions generally approximates the globally optimal solution.

For example, consider that you are given some random digits, say `1`, `4`, `2`, `6`, `9`, and `5`. Now you have to make the biggest number by using all the digits without repeating any digit. To create the biggest number from the given digits using the greedy strategy, we perform the following steps. Firstly, we select the largest digit from the given digits, and then append it to the number and remove the digit from the list until we have no digits left in the list. Once all the digits have been used, we get the...