Lesson IDs are Phase.Chapter.Topic. The order is a prerequisite chain. ✅ marks what you have marked as done.

🧭 PHASE 0 — FOUNDATIONS

• Ch 0.1 What a program is
• 0.1.1 Programs and instructions; source code → compiler → executable; the shape of a first C program (main, printf, return)
• 0.1.2 Memory as numbered boxes: bits, bytes, addresses; a variable as a named box
• L0.1 Chapter 0.1 Lock-in Lock-in
• Ch 0.2 Math toolkit
• 0.2.1 Powers of 2 and logarithms; floor and ceiling
• 0.2.2 Sums of series (1+2+…+n, 1+2+4+…+2ⁿ); basic counting
• L0.2 Chapter 0.2 Lock-in Lock-in
• CP0 Phase 0 Checkpoint Checkpoint

💻 PHASE 1 — PROGRAMMING IN C

• Ch 1.1 Data and expressions
• 1.1.1 Data types and their sizes; signed vs unsigned; constants; variables; declaration vs definition
• 1.1.2 Operators: arithmetic, relational, logical with short-circuiting, bitwise, assignment, ++ and --; precedence and associativity; undefined behavior
• 1.1.3 Type conversion: implicit promotion, casting, overflow, char as a small integer; what printf returns
• L1.1 Chapter 1.1 Lock-in Lock-in
• Ch 1.2 Control flow
• 1.2.1 if / else if / else; nested conditions; switch and fall-through
• 1.2.2 for, while, do-while; break and continue; tracing loop output and counting iterations
• L1.2 Chapter 1.2 Lock-in Lock-in
• Ch 1.3 Functions
• 1.3.1 Declaring, defining, calling; parameters; return values; call by value
• 1.3.2 Scope vs lifetime; local, global, static, extern, register; shadowing in blocks; static local variables
• 1.3.3 How calls work: the call stack and stack frames
• L1.3 Chapter 1.3 Lock-in Lock-in
• Ch 1.4 Pointers
• 1.4.1 & and *; pointer declaration; NULL; pointer to pointer
• 1.4.2 Simulating call by reference with pointers (swap)
• 1.4.3 Pointer arithmetic and why it scales by type size
• L1.4 Chapter 1.4 Lock-in Lock-in
• Ch 1.5 Arrays and strings in C
• 1.5.1 1-D arrays; a[i] == *(a+i) == i[a]; arrays decaying to pointers; passing arrays to functions; the sizeof trap
• 1.5.2 2-D arrays; row-major layout; pointer to array vs array of pointers; reading complex declarations
• 1.5.3 Strings: char arrays, '\0', read-only string literals, strlen vs sizeof, string functions and tracing string code
• L1.5 Chapter 1.5 Lock-in Lock-in
• Ch 1.6 Structures, unions, typedef
• 1.6 Structures, unions, typedef; self-referential structures; structure size and padding
• L1.6 Chapter 1.6 Lock-in Lock-in
• Ch 1.7 Dynamic memory
• 1.7 Dynamic memory: malloc, calloc, realloc, free; stack vs heap; dangling pointers, memory leaks, double free
• L1.7 Chapter 1.7 Lock-in Lock-in
• Ch 1.8 Preprocessor and function pointers
• 1.8 Preprocessor macros and their expansion traps; function pointers
• L1.8 Chapter 1.8 Lock-in Lock-in
• CP1 Phase 1 Checkpoint Checkpoint

🔁 PHASE 2 — RECURSION

• Ch 2.1 Recursion
• 2.1.1 Base case and recursive case; tracing calls on the stack
• 2.1.2 Recursion trees; counting calls; work done before vs after the recursive call
• 2.1.3 Classic patterns: factorial, Fibonacci, GCD, power, Tower of Hanoi (2ⁿ−1 moves), digit/array recursion
• 2.1.4 Computing what a recursive function returns via its recurrence; static and global variables inside recursion
• L2.1 Chapter 2.1 Lock-in Lock-in
• Ch 2.2 Counting work: a Big-O primer
• 2.2 Counting work: a Big-O primer
• L2.2 Chapter 2.2 Lock-in Lock-in
• CP2 Phase 2 Checkpoint Checkpoint

📚 PHASE 3 — LINEAR DATA STRUCTURES

• Ch 3.1 Arrays as a data structure
• 3.1 Arrays as a data structure: the ADT idea; address calculation (row-major, column-major, non-zero lower bounds); cost of insert, delete and search
• L3.1 Chapter 3.1 Lock-in Lock-in
• Ch 3.2 Stacks
• 3.2.1 Stack ADT; push/pop/peek; array implementation; overflow and underflow
• 3.2.2 Stack applications: parenthesis matching; infix → postfix/prefix conversion; postfix evaluation
• 3.2.3 Valid stack permutations; Catalan numbers
• L3.2 Chapter 3.2 Lock-in Lock-in
• Ch 3.3 Queues
• 3.3.1 Queue ADT; linear array queue and its wasted-space problem
• 3.3.2 Circular queue: full/empty conditions and index arithmetic
• 3.3.3 Deque; priority queue as a concept; queue from two stacks and stack from two queues (operation costs)
• L3.3 Chapter 3.3 Lock-in Lock-in
• Ch 3.4 Linked lists
• 3.4.1 Singly linked list: node, head, traversal, search, insertion (head/tail/middle), deletion
• 3.4.2 Reversing a list (iterative and recursive); finding the middle; detecting a cycle (fast/slow pointers)
• 3.4.3 Doubly and circular linked lists; operation costs compared with arrays
• 3.4.4 Stack and queue built on linked lists
• 3.4.5 GATE drill: tracing pointer-manipulation code on linked lists
• L3.4 Chapter 3.4 Lock-in Lock-in
• CP3 Phase 3 Checkpoint Checkpoint

🌳 PHASE 4 — TREES & BINARY SEARCH TREES

• Ch 4.1 Tree vocabulary
• 4.1 Tree vocabulary: root, parent, child, sibling, leaf, internal node, degree, level, depth, height; the edges-vs-nodes convention
• L4.1 Chapter 4.1 Lock-in Lock-in
• Ch 4.2 Binary trees
• 4.2.1 Strict/full, complete and perfect binary trees
• 4.2.2 Binary tree properties: nodes per level and height; n₀ = n₂ + 1; minimum and maximum height
• 4.2.3 Representations: linked nodes vs array indexing (both 0-based and 1-based formulas)
• L4.2 Chapter 4.2 Lock-in Lock-in
• Ch 4.3 Traversals
• 4.3.1 Preorder, inorder, postorder (recursive code and hand tracing)
• 4.3.2 Level-order traversal using a queue
• 4.3.3 Rebuilding a tree from two traversals; counting distinct binary trees (Catalan)
• L4.3 Chapter 4.3 Lock-in Lock-in
• Ch 4.4 Recursive code on trees
• 4.4 Recursive code on trees: count nodes, leaves, height, mirror, sums; expression trees
• L4.4 Chapter 4.4 Lock-in Lock-in
• Ch 4.5 Binary search trees
• 4.5.1 The BST property; search, minimum, maximum; inorder gives sorted order
• 4.5.2 BST insertion; building a BST from an insertion sequence; best- vs worst-case height
• 4.5.3 BST deletion: leaf, one child, two children (inorder successor or predecessor)
• 4.5.4 BST GATE drills: BST from a preorder/postorder sequence; number of BSTs; valid search paths; insertion orders giving the same BST
• L4.5 Chapter 4.5 Lock-in Lock-in
• Ch 4.6 Balanced BSTs (AVL)
• 4.6 Balanced BSTs — AVL idea, balance factor, rotations, minimum nodes for a given height
• L4.6 Chapter 4.6 Lock-in Lock-in
• CP4 Phase 4 Checkpoint Checkpoint

⛰️ PHASE 5 — BINARY HEAPS

• Ch 5.1 The heap idea
• 5.1 The heap idea: a complete binary tree in an array; max-heap and min-heap
• L5.1 Chapter 5.1 Lock-in Lock-in
• Ch 5.2 Insertion and deletion
• 5.2 Heap insertion (sift-up) and deleting the root (sift-down)
• L5.2 Chapter 5.2 Lock-in Lock-in
• Ch 5.3 Build-heap and heap sort
• 5.3 Build-heap in O(n) vs n insertions; heap sort
• L5.3 Chapter 5.3 Lock-in Lock-in
• Ch 5.4 Heap GATE drills
• 5.4 Heap GATE drills: k-th largest, number of heaps, comparisons, d-ary heaps
• L5.4 Chapter 5.4 Lock-in Lock-in
• CP5 Phase 5 Checkpoint Checkpoint

🕸️ PHASE 6 — GRAPHS

• Ch 6.1 Graph vocabulary
• 6.1 Graph vocabulary
• L6.1 Chapter 6.1 Lock-in Lock-in
• Ch 6.2 Representations
• 6.2 Graph representations: adjacency matrix, adjacency list, incidence matrix
• L6.2 Chapter 6.2 Lock-in Lock-in
• Ch 6.3 Traversals
• 6.3 Graph traversals: BFS, DFS, connected components
• L6.3 Chapter 6.3 Lock-in Lock-in
• CP6 Phase 6 Checkpoint Checkpoint

🏁 PHASE 7 — INTEGRATION & FINAL TEST

• Ch 7.1 Master Rule Sheet
• 7.1 Master Rule Sheet
• Ch 7.2 Mixed practice
• 7.2.1 Mixed practice set 1
• 7.2.2 Mixed practice set 2
• 7.2.3 Mixed practice set 3
• Ch 7.3 GATE pattern drill
• 7.3 GATE pattern drill
• Ch 7.4 Final test
• 7.4 Final end-to-end test Final test

Phases

🧭

Phase 0 · Foundations

4 lessons · 2 lock-ins · checkpoint

💻

Phase 1 · Programming in C

17 lessons · 8 lock-ins · checkpoint

🔁

Phase 2 · Recursion

5 lessons · 2 lock-ins · checkpoint

📚

Phase 3 · Linear Data Structures

12 lessons · 4 lock-ins · checkpoint

🌳

Phase 4 · Trees & Binary Search Trees

13 lessons · 6 lock-ins · checkpoint

⛰️

Phase 5 · Binary Heaps

4 lessons · 4 lock-ins · checkpoint

🕸️

Phase 6 · Graphs

3 lessons · 3 lock-ins · checkpoint

🏁

Phase 7 · Integration & Final Test

0 lessons · 0 lock-ins

🧭Phase 0 — Foundations