The program begins by defining a new MPI type which corresponds to a particle. Then all nodes exchange information with one another about the number of particles each of the nodes is responsible for. Appropriate number of particles are initialised by each node separately, and then the information and exact data about the particles are exchanged between the nodes. This way every node has access to information about all particles, which allows it to evaluate forces that act on the particles they are responsible for. Once the forces have been evaluated the program exits.