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From various sources (one being this), I've heard that quantum computers find the correct answer in a sea of possible ones by destructively interfering the wrong ones with each other, and the right one keeps building on itself. How does this work? Does every wrong answers have an opposite, but still wrong, answer? How can the correct answer not? Or am I completely misled here?
EDIT: This question differs form this because an answer to my previous question tells me about quantum interference to solve this problem, but does not explain how, and neither does the links.