Create Miller-Rabin_primalityTest.cpp

[Swish78]

This code checks if a given number is likely to be a prime using the Miller-Rabin primality test, which is a probabilistic algorithm. The algorithm chooses a random number and tests whether it is a witness for the compositeness of the given number. This is repeated a number of times to increase the confidence in the result. If the number passes all tests, it is considered likely to be prime.

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