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+# Pagerank Algorithm
+
+## Repository
+
+This repository provides a serial implementation of the pagerank algorithm in C language, as well as a parallel equivalent using OpenMP. The project was undertaken as part of the "Parallel and distributed systems" course of AUTH university.
+
+The code was tested for different data sets and information regarding the execution time and correctness were extracted.
+
+## Dependencies
+
+Only a compiler is needed (e.g. gcc).
+
+## Compilation
+
+To compile just run:
+
+```sh
+$ make
+```
+
+## Usage
+
+Run the code with the command:
+```sh
+$ ./pagerank [-c convergence_criterion] [-m max_iterations] [-a alpha] [-v] [-h] [-o output_filename] <graph_file>
+```
+where:
+
+ 1. **convergence_criterion** is the convergence tolerance criterion
+ 2. **max_iterations** is the maximum number of iterations to perform
+ 3. **alpha** is the damping factor
+ 4. **-v** enables verbal output
+ 5. **-h** enables history output to file
+ 6. **output_filename** is the output filename and path
+ 7. **graph_file** is the dataset filename and path
+
+The parallel version also provides the option -t number_of_threads where **number_of_threads** is the number of threads to use.