Programming Recursion — Study Path Agent

Chapter 1

Prerequisites: Functions, Scope, and Call Stack Basics

1

Functions & parameter passing (by value/reference)

2

Variable scope & lifetime (local vs global)

3

Call stack mental model (frames, return addresses)

Chapter 2

Core Recursion Concepts

4

Base cases & termination (avoiding infinite recursion)

5

Recursive case design (reduce the problem size)

6

Tracing recursion (stack traces, dry runs, recursion trees)

7

Return values vs side effects in recursive functions

8

Complexity intuition for recursion (time/space, recursion depth)

Chapter 3

Common Recursive Patterns

9

Linear recursion (countdown, sum, factorial)

10

Divide-and-conquer recursion (binary search, merge sort idea)

11

Structural recursion on data (lists, arrays, strings)

12

Tree recursion (traversals and branching recursion)

3 subtopics

13

Binary tree traversals (pre/in/post-order) using recursion

14

DFS on graphs using recursion (visited set basics)

15

Backtracking template (choose → explore → unchoose)

16

Mutual recursion (two functions calling each other)

17

Generating combinations/permutations recursively

Chapter 4

Recursion in Data Structures & Algorithms

18

Recursive linked list operations (reverse, nth node, merge)

↗ Tree recursion (traversals and branching recursion) (see Chapter 3)

19

Recursive sorting & searching (merge sort/quicksort, binary search)

20

Recursive dynamic programming (top-down memoization)

3 subtopics

21

Memoization with a map/array (key design)

22

Classic DP problems (Fibonacci, coin change, knapsack) in recursive form

23

Overlapping subproblems vs optimal substructure (recognition)

24

Recursive parsing basics (nested parentheses / expression evaluation idea)

Chapter 5

Making Recursion Practical (Optimization & Limits)

25

Tail recursion & tail-call optimization (when it applies)

26

Converting recursion to iteration with an explicit stack

2 subtopics

27

Simulating DFS iteratively (stack push/pop patterns)

28

Managing state for backtracking iteratively (frames/state objects)

29

Stack overflow & recursion depth limits (language/runtime considerations)

30

Debugging recursive code (breakpoints, logging, invariants)

Chapter 6

Practice & Mastery Checklist

31

Write 10 recursive functions with clear base/recursive cases (drills)

32

Trace 10 recursion examples by hand (stack frames + returns)

33

Solve 10 backtracking problems (subsets, permutations, N-Queens)

34

Convert 5 recursive solutions to iterative (explicit stack)

35

Add memoization to 5 recursive problems and compare complexity

36

Implement recursive tree traversals and validate outputs with tests