What is the difference between a quantum algorithm and a classical one?

Question

Programming

How does a quantum algorithm differ from a classical one? Will the classical approach to programming become obsolete if quantum computing enters the mainstream?

Answer 1

In the classical algorithm, a specific state of the computer (deterministic) is implemented.
In a quantum computer, there are simultaneously many states of the machine that exist simultaneously and immediately.
The solution of the problem on a quantum computer is the distribution of the probability of occurrence of a "specific" state for "specific" input data. That. in a quantum computer, you cannot get an exact solution, but you can get as close to it as you like (performing several calculations).

Answer 2

What is the difference between a quantum algorithm and a classical one?
- those that are intended for a quantum computer and work not according to the laws of Boolean arithmetic, but according to the laws of quantum information theory.
- Will the classical approach to programming become obsolete if quantum computing enters the mainstream?
- All quantum mechanical algorithms are currently highly specialized. I don't think you need to worry about it. Your grandchildren may catch this moment.