Sentinel Stream Data Filter

This project implements a data processing algorithm in C that analyzes a stream of integers provided by the user. It functions as a Conditional Filter that aggregates statistics based on the magnitude (number of digits) of the input.

⚙️ Algorithm Logic

The system uses a Sentinel-Controlled Loop structure, meaning the iteration count is not fixed but determined by the data itself.

1. Input Stream: Continuously accepts integers from the standard input.
2. Termination Condition: Checks every input for the sentinel value (-1). If found, the data stream is considered closed.
3. Magnitude Analysis:
   • Decomposes the integer using iterative division (/ 10).
   • Calculates the digit count: $d = \lfloor \log_{10}|x| \rfloor + 1$.
4. Filtering & Aggregation:
   • Filter: if (digits == 2)
   • Action: Increment the global counter.

🚀 Usage Scenario

This logic is fundamental in systems where the amount of data is unknown beforehand (e.g., reading sensor data until a stop signal).

1. Compile the code:

   gcc main.c -o data_filter

2. Run the executable:

   ./data_filter

3. Enter various numbers. To stop the analysis and see the count of 2-digit numbers, enter -1.

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This repository demonstrates while-loops, sentinel logic, and numerical analysis in C.