Pseudo Lights Out Game

A modular, state-based C program inspired by the Lights Out puzzle

Source Code:
View the project on GitHub

Overview

The Pseudo Lights Out Game is a console-based application written in C, inspired by the classic Lights Out puzzle. The project was developed to explore modular software design, state-based logic, and structured programming in a low-level language.

The program simulates a house composed of multiple windows, each represented by a binary on/off state. Users interact with the system through single-character keyboard input, toggling individual windows while the application continuously updates and displays the current system state.

Unlike the traditional Lights Out game, this implementation does not include neighbor-based toggling. Instead, it functions as a deterministic state machine in which each window is toggled independently.

Software Design

The application is organized into multiple source and header files to enforce separation of concerns:

  • main.c – Program control loop and user interaction
  • house.c / house.h – House-level state management
  • window.c / window.h – Individual window state and toggle logic
  • ezinput.c / ezinput.h – Single-character, validated user input handling

This modular design improves readability, maintainability, and extensibility, and mirrors real-world software practices used in systems and embedded programming.

Game States

Initial State

At program startup, a subset of windows is enabled, resulting in the following initial configuration:

Initial State

Winning Input Sequence

While the program does not explicitly enforce a win condition in code, a “solved” state can be interpreted as all windows being turned off.

For the default starting configuration, the system reaches this solved state by toggling the following windows:

Winning input sequence: 4, 5, 7, 8, 9

Each input toggles the corresponding window’s state.

Final State

After applying the winning input sequence, all windows are turned off, resulting in the following final configuration:

Initial State

The program continues running until the user exits by entering 0.

Skills Demonstrated

  • Modular programming in C using multiple source and header files
  • State-machine logic and deterministic control flow
  • Structured data design using struct and function-based encapsulation
  • Robust user input handling and validation
  • Separation of concerns and maintainable software architecture
  • Debugging and iterative feature development in C