These are some of the codes I have written in C++. I have done the implementation of many data structures -

1. Trees (Binary + BST + Generic)
2. Hashmaps (problems + implementation)
3. Tries
4. Graphs
5. Some popular algorithms in graphs (Dijkstra's, Prim's..)
6. PriorityQueues (implementation + problems)
7. OOPS
8. Cartesian Tree
9. Linked Lists (implementation + utility functions + problems)
10. Dequeue (Class)
11. Sparse Matrix using: i) Arrays ii) Linked Lists iii) List of Lists iv) Maps(Dictionary)
12. K Stacks in a single array (space efficient method)
13. AVL Trees (Self Balancing BSTs), RB Trees, Treaps
14. Implementation of doubly linked lists (Circular)
15. Skip Lists (randomized data structures)