The Smart Code Autocomplete Engine is a C++ project designed to suggest intelligent code completions in real time — similar to how modern IDEs like VS Code or IntelliJ offer autocomplete suggestions. It applies core Data Structures and Algorithms (DSA) concepts such as Tries, Heaps, and LRU (Least Recently Used) caching to efficiently predict the next most probable code tokens based on user input frequency and context.
When a programmer starts typing part of a keyword or function name, the engine quickly: Searches through a Trie (prefix tree) for all words starting with that prefix. Uses a Heap to rank suggestions by frequency or relevance. Employs an LRU Cache to prioritize recently used or selected completions, making the system adaptive over time.
This results in fast, memory-efficient, and intelligent autocomplete suggestions that simulate the logic behind real-world code editors — but built purely from scratch using fundamental DSA concepts.
- Files: tst.h, tst.cpp, tst_test.cpp
- Used for storing and retrieving words efficiently based on their prefixes.
- Enables O(L) time complexity lookups (where L = length of prefix).
- Supports real-time suggestions as the user types each character.
🔹 Concepts used: String manipulation, recursion, tree traversal, prefix-based searching.
- Files: minheap.h, minheap.cpp, heap_test.cpp
- Maintains the top N most frequent or relevant words efficiently.
- Provides constant-time access to the best-ranked suggestion.
- Used during ranking and sorting of autocomplete results.
🔹 Concepts used: Binary heap operations, priority queue logic, partial sorting.
- Files: lru.h, lru.cpp, lru_test.cpp
- Stores recently used suggestions for quick access.
- Improves responsiveness by avoiding repetitive Trie lookups.
- Implemented using a combination of doubly linked list + hash map.
🔹 Concepts used: Linked lists, hashing, cache eviction policy.
- Files: kmp.h, kmp.cpp
- Used for efficient substring pattern matching between typed input and stored code tokens.
- Ensures fast lookup of partial matches even in large word lists.
🔹 Concepts used: Prefix table computation, linear-time pattern searching.
- Files: graph.h, graph.cpp
- Represents relationships between tokens or code components.
- Can model transitions between function calls or variable dependencies for context-aware suggestions.
🔹 Concepts used: Adjacency list representation, graph traversal (BFS/DFS).
- Files: stack.h, stack.cpp
- Used internally for recursive operations, backtracking, or maintaining function call hierarchies.
- Simplifies control flow during traversal or undo operations in text editing logic.
🔹 Concepts used: LIFO operations, template-based generic stack implementation.
- Files: ranker.h, ranker.cpp
- Combines frequency and recency scores from Trie, Heap, and LRU cache to rank autocomplete suggestions.
- Implements a weighted scoring system for realistic, adaptive predictions.
🔹 Concepts used: Comparator functions, dynamic sorting, frequency-based ranking.
- Files: freq_store.h, freq_store.cpp, frequency.txt
- Keeps track of how often each word is used.
- Updates dynamically after every suggestion selection, making the model “learn” over time.
🔹 Concepts used: File handling, hash mapping, frequency analysis.
- Insert code keywords or phrases
- Autocomplete suggestions based on prefix
- Suggestions ranked by frequency
- Snippet support (e.g.,
fori→for (int i = 0; i < n; i++)) - Combined suggestion pipeline (phrases, prefix, and substring matches) — returns up to 10 suggestions.
- Top-K ranking uses a MinHeap and frequency/co-occurrence signals; recent results are cached in an LRU for responsiveness.
- Editor behavior: files saved to
scratch/by default (created automatically) and Undo/Redo is supported (Ctrl+Z / Ctrl+Y). - Practical demonstration of Trie + Hash Map + Heap working together
| Category | Technologies / Tools | Description |
|---|---|---|
| Language | C++ (C++17 Standard) | Core implementation of all modules, data structures, and algorithms. |
| Build System | GNU Make (Makefile) | Used for compiling multiple source files and linking into a single executable. |
| Compiler | GCC / G++ | To compile and build the C++ source files efficiently. |
| Version Control | Git + GitHub | For code management, versioning, and collaboration among team members. |
| Testing Framework | Custom test files (tests/) |
Unit testing for core modules like Trie, LRU, and Heap. |
| Data Storage | Text files (data/words.txt, data/frequency.txt) |
Stores training words and their frequency for suggestion ranking. |
| Editor / IDE | VS Code | Primary development environment for coding, debugging, and project organization. |
- User enters keywords (e.g.,
print,printf,private, etc.) - Trie stores all words for fast prefix lookup
- Hash map tracks how often each word is used
- Heap finds the most frequent matches for a prefix
- Snippets expand small abbreviations into full code blocks
- Type:
pri - Suggestions:
print,printf,private(ranked) - Type:
fori - Expanded snippet:
for (int i = 0; i < n; i++)
If your project uses Python utilities or scripts (e.g., preprocessing):
- python3 -m venv dsavenv
- source dsavenv/bin/activate
- sudo apt update
- sudo apt install build-essential g++ libncurses-dev
Use the root Makefile.
Build the terminal editor:
make basic_editor
# produces `./basic_editor`If you prefer to compile the editor manually:
g++ -std=c++17 basic_editor.cpp \
src/tst.cpp src/phrase_store.cpp src/freq_store.cpp src/ranker.cpp src/graph.cpp \
src/minheap.cpp src/lru.cpp src/stack.cpp src/kmp.cpp \
-lncurses -Iinclude -o basic_editor-
Run the editor:
./basic_editor
Notes:
scratch/is created automatically bybasic_editorand is ignored by git; editor-saved local files will go there by default.- If you downloaded pre-built binaries and see errors about GLIBCXX or GLIBC versions, rebuild locally (e.g.,
make clean && make) to link against your machine's C++ runtime.
To verify components:
- g++ tests/heap_test.cpp -o heap_test && ./heap_test
- g++ tests/lru_test.cpp -o lru_test && ./lru_test
- g++ tests/tst_test.cpp -o tst_test && ./tst_test
- Code Editors (VS Code, JetBrains)
- Search Engines
- Chatbots
- AI-assisted development tools
| Name | Roll Number | GitHub |
|---|---|---|
| Tanisha Ray | B24CM1061 |  |
| Maahi Ratanpara | B24CS1040 |  |
| Anika Sharma | B24CM1009 |  |
| Akshita Maheshwari | B24CM1006 |  |
This project demonstrates the application of DSA in a real-world scenario — showing how core structures like tries, heaps, and caches can combine to form an intelligent system used in everyday developer tools. #test