For a faster processing, parallelisation is inevitable. In a first (and simple) approach, scan your code for prominent blocks of instructions that would benefit from multi- threading. Extend these blocks of instructions with valid OpenMP directives in order to allow a parallel processing. Run your code for different values of N (see above) and different amount of threads (2, 3, and 4). What do you observe now? For control, always print the largest prime number found!

for prime number