The prime factorization of a positive integer is a list of the integer's prime factors, together with their multiplicities; the process of determining these factors is called integer factorization. The fundamental theorem of arithmetic says that every positive integer has a single unique prime factorization.
The prime factorization of 24, for instance, is (2^3) * (3^1).
Write a class called PrimeFactorizer whose constructor takes no arguments and has an instance method factor accepting exactly 1 long which returns a Map<Long, Integer> where the keys are prime numbers and the values are the multiplicities.
new PrimeFactorizer().factor(24) //should return { 2 => 3, 3 => 1 }