PAGE RANK ALGORITM
Core assumpition:
-In order to save space we have a sparse matrix saved as array of pointer to a list. -We use this huge model of web https://snap.stanford.edu/data/web-NotreDame.html and so we have implemented a specific way to read this file
#DEMO.txt is a really small model that we used to validate our algoritm since we already knew the results
#Page_Rank_SERIAL.c = PageRank serial implementation according to google's algoritm https://www.youtube.com/watch?v=E9aoTVmQvok&list=PLLssT5z_DsK9JDLcT8T62VtzwyW9LNepV&index=12 for more info.
#Page_Rank_MPI.c = a parallel implementation using MPI library; we choose a master/worker architetture to distribuite the load // THIS IS A NOT PERFORMANCE SOLUTION TOO MANY MESSAGE
#Page_Rank_MPI_2.c =a parallel implementation using MPI library; we choose a master/worker architetture to distribuite the load OMPTIMIZED VERSION
how to run : main expect 2 arguments, the name of the file "./WEB.txt" in our case and the ID of the 1 node ( 0 or 1 )