1. Basic Recursion
·      Calculate the Factorial of a Number
·      Compute the Fibonacci Sequence
·      Calculate the Power of a Number (Exponentiation)
·      Print Numbers from 1 to N
·      Print Numbers from N to 1
·      Find the Sum of Natural Numbers up to N
·      Calculate the GCD (Greatest Common Divisor) of Two Numbers
·      Check if a String is a Palindrome
·      Find the nth Triangular Number
·      Count the Number of Digits in a Number
 
 2. Recursion on Arrays and Lists
·      Find the Maximum Element in an Array
·      Find the Minimum Element in an Array
·      Sum of All Elements in an Array
·      Find the Index of a Target Element in a Sorted Array (Binary Search)
·      Count Occurrences of a Target Element in an Array
·      Reverse an Array
·      Merge Two Sorted Arrays
·      Find the Subsets of an Array
·      Generate Permutations of an Array
·      Generate Combinations of an Array
 
 3. Recursion on Strings
·      Print All Substrings of a String
·      Generate All Permutations of a String
·      Generate All Combinations of a String
·      Find All Palindromic Substrings in a String
·      Implement String Compression
·      Find the Longest Palindromic Subsequence
·      Find the Minimum Number of Palindromic Partitions
·      Check if a String Matches a Pattern with Wildcards
·      Remove All Adjacent Duplicates from a String
·      Convert a String to an Integer (String to Integer Conversion)
 
 4. Recursion in Trees
·      Traverse a Binary Tree (In order, Preorder, Post order)
·      Calculate the Height of a Binary Tree
·      Find the Maximum Depth of a Binary Tree
·      Check if a Binary Tree is Balanced
·      Count the Number of Nodes in a Binary Tree
·      Find the Lowest Common Ancestor of Two Nodes
·      Find All Paths from Root to Leaf in a Binary Tree
·      Convert a Binary Search Tree to a Doubly Linked List
·      Check if Two Trees are Identical
·      Find the Diameter of a Binary Tree
 
 5. Recursion in Graphs
·      Perform Depth-First Search (DFS) on a Graph
·      Perform Breadth-First Search (BFS) Using Recursion
·      Find All Connected Components in a Graph
·      Detect a Cycle in a Graph Using DFS
·      Find the Shortest Path in a Graph Using DFS
·      Solve the N-Queens Problem
·      Solve the Rat in a Maze Problem
·      Find All Hamiltonian Paths in a Graph
·      Find All Eulerian Paths in a Graph
·      Solve the Subset Sum Problem