DSA

Binary Tree - BT

S.No.	Problem	Approach/Logic used	Level	Link	Solution
1	Build Tree Recursively		Easy	view	view
2	Count Leaf Nodes	traverse the tree through any traversal technique and just check one condition if the node has no left subtree and no right subtree then increase the count	Easy	view	view
3	Tree Traversals		Easy	view	view
4	BT Representation		Easy	view	view
5	Height of Binary Tree		Easy	view	view
6	Diameter/width of a BT		Medium	view	view
7	Balanced Tree or Not		Easy	view	view
8	Tree Identical or Not		Easy	view	view
9	Sum Tree or Not		Medium	view	view
10	BT Level Order Traversal		Medium	view	view
11	Sum of Longest Bloodline		Medium	view	view

Binary Search Tree - BST

S.No.	Problem	Approach/Logic used	Level	Link	Solution
1	Validate BST		Easy	view	view
2	Two sum in BST		Medium	view	view
3	Flatten BST to Sorted Linked List		Medium	view	view
4	Normal BST to Balanced BST		Medium	view	view
5	Merge two BSTs		Medium	view	view
6	Largest BST in a BT		Hard	view	view

Heaps

S.No.	Problem	Approach/Logic used	Level	Link	Solution
1	Insertion and Deletion in Heap			view	view
2	Build Min Heap		Easy	view	view
3	Heap Sort		Medium	view	view
4	Merge two heaps		Easy	view	view
5	Convert BST to Max Heap	bst property(inorder of bst is sorted) and postorder has been used	Medium	view	view
6	Kth Smallest	using priority queue as maxheap	Easy	view	view
7	Is BT Heap	Heap follows two properties that's heap should be a CBT(complete BT) and should follow heap order property either max/min heap order	Medium	view	view
8	kth largest sum subarray	two approaches, one is using nested for loop and another one is using min heap	Medium	view	view
9	Merge K Sorted Arrays	two approaches	Medium	view	view
10	Smallest Range from K sorted list	3 approaches	Hard	view	view
11	Median in a Stream	two approaches, one is bruteforce and another is using min and max heaps	Hard	view	view

Graph DS

S.No.	Problem	Approach/Logic used	Level	Link	Solution
1	Implementation of graph using Adjacency List			view	view
2	Implementation of graph using Adjacency Matrix			view	view
3	Creating and Printing		Easy	view	view
4	BFS in Graph		Medium	view	view
5	DFS in Graph		Medium	view	view
6	Cycle Detection in Undirected Graphs using BFS	BFS and a condition visited[neighbour]==true and neighbour!=parent[front]	Medium	view	view
7	Cycle Detection in Undirected Graphs using DFS	DFS and a condition visited[neighbour]==true and neighbour!=parent	Medium	view	view
8	Cycle Detection in directed Graphs using DFS		Medium	view	view
9	Topological Sort		Medium	view	view
10	TopoSort using Kanh's algo		Medium	view	view
11	Cycle Detection in directed graph using TopoSort		Medium	view	view
12	Shortest Path in Undirected graph		Medium	view	view
13	Shortest Path in DAG		Medium	view	view