Rest 2.0

John was previously settling all the questions proposed by his colleague, which made him very angry. Such a "colleague" believed that John was getting the questions right because the first number, in this case A, was not so big. So, he took a sheet and filled it whole, with just one number, representing A. As he thought it would be impossible to discover such an answer with this gigantic number, he asked one of his friends to choose a second number, this time without exaggeration, to represent B.

As John knows many mathematical theories, this challenge was not at all difficult for him and he found the rest of the A ÷ B division with all the precision and certainty of the world.

Your task is to report the number that John found by calculating the remainder of the division of A ÷ B, since you are the only person he told the answer to.