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Home Courses Theory of Computation Course materials Lectures 4.A: Reductions and direct reduction

4.A: Reductions and direct reduction

Course week(s) Week 4
Course subject(s) 4: Reducibility

Description: Reduction is a technique to prove that a problem is undecidable (or unrecognisable) by converting it into another problem of which it is known that is undecidable (or unrecognisable). The most “direct” way to reduce problems to other problems is called “direct reduction”. Some problems are shown to be undecidable by using this technique.

Book: Introduction to the Theory of Computation, Chapter 5, pp. 191-195.

Exercise: 5.2

Key concepts:

  • Direct Reduction
Module 4A
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