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Learn Recursion with visual DSA lessons

Learn Recursion with 5 DSA patterns and 20 visual lessons. Follow step-by-step animations and synced C#, Python, and Java code.

Recursion asks a smaller version of the same problem for help.

Linear Recursion

Make one smaller recursive call until the base case is reached.

Factorial of N Easy · Visible call stack
Print 1 to N / N to 1 Easy · Visible call stack
Check Palindrome (Recursive) Easy · Visible call stack
Pow(x, n) Medium · Visible call stack

Non-Linear Recursion

Make multiple smaller calls and combine their returned answers.

Fibonacci Number Easy · Visible call stack
Climbing Stairs Easy · Visible call stack
Unique Paths Medium · Visible call stack
House Robber / Stickler Thief Medium · Visible call stack

Divide & Conquer

Split the input, solve each part, then combine the answers.

Binary Search (Recursive) Easy · Visible call stack
Merge Sort Medium · Visible call stack
Quick Sort Medium · Visible call stack
Power (xⁿ) Medium · Visible call stack
Median of Two Sorted Arrays Hard · Visible call stack

Recursion on LinkedList/Stack

Handle one node or stack item and recurse on the remaining structure.

Reverse Linked List Easy · Visible call stack
Merge 2 Sorted Lists Easy · Visible call stack
Delete Middle of Stack Easy · Visible call stack
Reverse Stack Medium · Visible call stack

Subsequences

For every value, choose to include it or skip it.

Generate All Subsets Medium · Visible call stack
Subset Sum Medium · Visible call stack
Count Subsequences with Given Sum Medium · Visible call stack