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 # Readme exercice 4
 
 code by Marti Bosch (marti.bosch@epfl.ch) and Marc Schwaerzel (marc.schwaerzel@epfl.ch) 
 
 ## Exercise 1
 
 ## Exercise 2
+2.2 We will probably have to use a shared pointer in order that the memory is managed well?!
+2.3 I used the method where I put setters but there is a way to access private members --> reread class notes and implement them
 
 ## Exercise 3
 
-## Exercise 4
-
 
 ## Instructions to run the code
 
 To run the code follow the instructions:
 
 1) Create a new directory in the exercice_4 directory and go into that folder:
 	
 	$ mkdir build
 	$ cd build
 
 2) Check whether your paths are set correctly
 
 	$ ccmake ../
 
 2) Compile the code:
 	
 	$ cmake ../
 	$ make
 
 3) Then run as follows
 
 	$ ./particles --help
     
     Usage: ./particles nsteps dump_freq input.csv particle_type timestep
 	    particle type can be: planet, ping_pong, material_point