C Challenges: Professional Level Problem Solving

These challenges simulate real-world coding problems where you must balance speed, memory, and code safety.

Challenge 1: The Custom String Parser

The Scenario: You are building a light-weight web server. You need to parse a "Query String" from a URL without using heavy external libraries.

• Task: Given a string like "name=Gemini&age=2&status=active", extract the values and print them.
• Constraint: You cannot use strtok(). You must use pointers and manually find the = and & symbols.
• Goal: Master pointer arithmetic and string safety.

Challenge 2: The Memory Leak Detective

The Scenario: You are managing a dynamic list of sensor readings. Data comes in every second, and you must store it in a growing array.

• Task: Start with an array of size 2. Every time it gets full, use realloc() to double its size.
• Constraint: If realloc() fails, you must not lose the original data. You must also free all memory at the end.
• Goal: Learn safe dynamic memory management and the "Heap" lifecycle.

Challenge 3: The Bit-Packed Flags

The Scenario: You are working on a low-power IoT device with only 1 byte (8 bits) of RAM available for status updates.

• Task: Store 8 different "On/Off" settings (e.g., Power, WiFi, Bluetooth, GPS, etc.) inside a single uint8_t variable.
• Constraint: Write a function toggle_bit(int position) and check_bit(int position) using Bitwise XOR and AND.
• Goal: Extreme memory optimization using Bit Manipulation.

Challenge 4: The Circular Buffer (Advanced)

The Scenario: In audio processing, data streams constantly. A "Circular Buffer" allows you to overwrite the oldest data once the array is full.

• Task: Create an array of size 5. As you add the 6th element, it should automatically replace the 1st element.
• Constraint: Use the Modulo operator (%) to manage the index wrap-around.
• Goal: Understand data stream structures and index logic.

Challenge 5: The "Big Endian" vs "Little Endian" Test

The Scenario: Different CPUs store data differently. You need to write a program that detects how the current computer stores an integer.

• Task: Use a character pointer to look at the first byte of a multi-byte integer.
• Constraint: Do not use any built-in system macros.
• Goal: Learn about system architecture and memory mapping.

Challenge	C Concept Tested
String Parser	Pointer Arithmetic
Memory Detective	Dynamic Allocation (Heap)
Bit-Packed Flags	Bitwise Operators