How do I start learning or strengthen my knowledge of data structures and algorithms?

How do I learn data structures and algorithms?

I was in the same situation 1 and a half year ago. I will explain how I learnt data structure and algorithms. 

In the following text Algorithms and Data structure which are marked in bold are very important. Learn every algorithm/data structure with it’s time & space complexity, stable, in place, and where it is useful.

 
What to study?
Step 0 :

• Understand about pointers in C++, structures or classes
• Learn how to calculate worst case, best case , average case time complexities

Step 1 :

Learn few basic sorting algorithms along with their use case and time complexity.

• Bubble sort
• Insertion sort
• Selection sort

Learn searching algorithms along with time complexity.

• Linear Search
• Binary Search

Step 2 :

• Stack
• Queue
• Single Linked List (Insert at front,back,middle; Delete at front back middle)
• Double Linked List
• Circular Linked List

Step 3 :

• Learn the following approaches in algorithms
• Divide and Conquer (Merger Sort, Quick Sort, Binary Search are some examples)
• Greedy method (Knapsack, Prim’s algorithm, Kruskal’s algorithm, Dijkstra, Bellmanford)
• Dynamic programming (0/1 Knapsack, Travelling Salesman Problem, Coin change)
• Backtracking (N Queens problem)

Step 4 :

• Binary Tree
• Binary Search Tree
• Height of a Tree
• Tree Traversal
• BFS
• DFS
• Searching an element
• AVL Tree
• Hashing

Where to study from? 

GeeksforGeeks | A computer science portal for geeks
Data Structures and Algorithms | Coursera
LeetCode - The World's Leading Online Programming Learning Platform
Logicmojo | Video Lectures
Video Lectures | Introduction to Algorithms (SMA 5503) | Electrical Engineering and Computer Science | MIT OpenCourseWare
Online Courses - Learn Anything, On Your Schedule | Udemy