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WikiCards · Card list · Science cards · NP-hardness
Uncommon card · Science
NP-hardness, an Uncommon card
In computational complexity theory, a computational problem H is called NP-hard if, for every problem L which can be solved in non-deterministic polynomial-time, there is a polynomial-time reduction from L to H.
- Rarity
- Uncommon
- Domain
- Science
- ATK
- 54
- DEF
- 29
- Power
- 83
- Wikipedia reads a year
- 120,000
Power 83 (ATK + DEF): stronger than 25 % of WikiCards cards.
NP-hardness quiz: 3 questions
Three questions on the NP-hardness card, the way WikiCards duels ask them. Pick an answer, the facts are just below.
Find the missing word
A simple example of an NP-hard problem is the ______ sum problem.
Answer
subset. A simple example of an NP-hard problem is the subset sum problem. From the NP-hardness article on Wikipedia.
Which of these cards hits hardest (highest ATK)?
Answer
NP-hardness. NP-hardness 54 · Daniel Núñez del Prado 51 · WFDC5 46 · FRAT2 43 ATK in WikiCards.
Which of these Wikipedia articles is read the most in a year?
Answer
Newton. Newton 220,000 · NP-hardness 120,000 · WFDC5 190 · Daniel Núñez del Prado 60 Wikipedia reads over a year.
In a duel, each round asks a question like these about the opposing card, with 15 seconds to answer.
The facts on the card
The card carries these facts from its Wikipedia article.
- As a consequence, finding a polynomial time algorithm to solve a single NP-hard problem would give polynomial time algorithms for all the problems in the complexity class NP.
- As it is suspected, but unproven, that P≠NP, it is unlikely that any polynomial-time algorithms for NP-hard problems exist.
- A simple example of an NP-hard problem is the subset sum problem.
Why it is Uncommon
Rarity in WikiCards follows a year of Wikipedia page views: the most read articles become Epic and Legendary cards. The NP-hardness article was read about 120,000 times in a year. ATK comes from the length of the article and DEF from its quality, so this card hits with 54 and blocks with 29: each hit it takes is cut by 12 %.
How to get NP-hardness
Open packs. Each pack holds five cards drawn from real Wikipedia articles, the rarest last, and the fifth card is always Rare or better. The odds are shown in the game. A free pack arrives every hour and two can wait, and the Coins you win in duels buy more packs.
More Science cards
Cards close in power
The cards just above and just below NP-hardness in the power ranking, all domains together.
- Erick SermonUncommon · Arts · ATK 54 DEF 29
- Sib HashianUncommon · Arts · ATK 52 DEF 31
- Steve AgeeUncommon · Arts · ATK 57 DEF 26
- Big RipUncommon · Science · ATK 57 DEF 26
- Black turtle beanUncommon · Society · ATK 47 DEF 36
- DiprotodontiaUncommon · Nature · ATK 57 DEF 26
Card lists
- Wikipedia quizNew questions every day
- All cards from A to ZEvery card, by name
- Science cards
- Legendary cards
- Tier listS and A tiers by power (ATK + DEF)
Credits
Text : Wikipedia, NP-hardness (revision), CC BY-SA 4.0. Photo : Behnam Esfahbod, CC BY-SA 3.0, Wikimedia Commons.
