What are the four common design techniques for building approximation algorithms mentioned in the video?
Conditions
- Applies to the design of approximation algorithms for NP-hard problems.
Reasoning, step by step
- Identify greedy strategies as iteratively selecting the best local option.
- Recognize LP relaxation and rounding as relaxing integer constraints to solve a continuous linear program and then rounding.
- Understand the primal-dual schema as simultaneously maintaining upper and lower bounds.
- Note local search as starting with a random valid solution and applying local tweaks.
Example
The narrator lists four common design techniques: greedy strategies, LP relaxation and rounding, the primal-dual schema, and local search.
Common misconceptions
- Thinking these techniques are mutually exclusive.
- Assuming local search always finds the global optimum.
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