system
Given the following post, respond as if you're commenting on Reddit:
human
How does one read information from qubits?

When the qubits are being read by the outside world, they would collapse - how do we make sure they collapse so that the information is accurate?
gpt
This is the entire challenge of creating quantum algorithms, and there's no set method. The way that you manipulate your qubits will vary depending on what sort of problem you're solving. The basic idea, though, is that since quantum states can interfere with each other, you arrange it so that states corresponding to correct answers constructively interfere, while states corresponding to incorrect answers destructively interfere.

The simplest quantum algorithm is probably the Deutsch-Josza algorithm, which solves the following problem: Given a function that takes as its argument a string of 1s and 0s of length n and outputs either a 1 or a 0, and given that this function is either a) constant, meaning it gives the same result for all inputs, or b) balanced, meaning it returns a 1 for exactly half the possible inputs and 0 for the others, how can you tell which of a) or b) is correct?

The solution is essentially to take n qubits, in a superposition of all possible states, and manipulate them so that any state that returns a 1 picks up a negative phase shift, while any state that returns a 0 is unchanged. If the function is balanced, then the half of the states with a negative phase shift will exactly cancel out with the other half that are unchanged, whereas if it's constant, all states have the same phase and so all reinforce, and this is set up to be linked to the probability of measuring a particular state, where all the qubits are 0, in the output. So you measure the output, and if you get all 0s, then you know it's constant, and if you get anything else, you know it's balanced.

This is a simplification, but it should give at least a sense of how it works.