# Quantum Computing Challenge References - Completed

Below you will find a list of reference materials that we have gathered for you to indulge in.## Quantum Annealing 101

Fujitsu’s Digital Annealer (DA) is inspired by the Quantum Annealing methodology. It can efficiently solve the most difficult problems that classic computers cannot. DA is a specially designed system that is different from the normal CPU based computer which can solve complex problems using the Annealing algorithm.Keep these points in mind when solving problems using the Annealing technique:

Annealing is an algorithm technique for approximating the global optimum of a given function.

DA will solve the problem using a specific system that can process and give the results of annealing algorithms.

DA can solve problems that can be modeled as a Quadratic Unconstrained Binary Optimization (QUBO) problem, which is a variation of the Ising model.

The key to solving a problem in DA is to transform the specific problem into a correct QUBO and then send this QUBO formulation to DA.

Digital Annealer is capable of solving up to 8192 bits of problem space, meaning the DA API can return results of 8192 bits.

You will learn more about Ising Model and QUBO as you proceed with the learning challenges, but in short, you will be providing mathematical equations to solve problems.