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dhemmy
how do you test for primality in java. and if the input is not prime how do you output the product
Use the modulus (%) operator. If 0 the number is even, if not it is odd. Discard number if even (and not 0, depending on how you look at it), then for all odd numbers write a recursive method that breaks down the number into its factors
For primality there are many different sieves that allow one to find prime numbers up to a given number; you can just use trial division and see if any of these divide your given number.