In Schor's algorithm, the quantum computer finds the period p of B mod N were N is the number you are trying to factor and B is a random number less than N. Th

In Schor's algorithm, the quantum computer finds the period p of B mod N were N is the number you are trying to factor and B is a random number less than N. The quantum computer may find p with imperfect accuracy. Running the algorithm repeatedly can improve the accuracy of p. You can also try other numbers close to p. Both are examples of error correcting a quantum algorithm.