Welcome to the simulation of Shor's algorithm. There are four restrictions for Shor's algorithm: 1) The number to be factored must be >= 15. 2) The number to be factored must be odd. 3) The number must not be prime. 4) The number must not be a prime power. There are efficient classical methods of factoring any of the above numbers, or determining that they are prime. Input the number you wish to factor. 17 Step 1 starting. Error, the number must not be prime!