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Discussion
Yolanda said This seemed like a very short chapter, at least it did to me. Bob agreed Yes, but the professor indicated that the goal was just provide some key examples.
Discussion
Yolanda said This seemed like a very short chapter, at least it did to me. Bob agreed Yes, but the professor indicated that the goal was just provide some key examples. I think he was hinting at more general notions of inversionalthough I haven't a clue as to what they might be.
Clearly aggravated, Zori said I've had all I can stand of this big integer stuff. This won't help me to earn a living. Xing now was uncharacteristically firm in his reply Zori. You're off base on this issue. Large integers, and specifically integers which are the product of large primes, are central to public key cryptography. If you, or any other citizen, were highly skilled in large integer arithmetic and could quickly factor integers with, say \(150\) digits, then you would be able to unravel many important secrets. No doubt your life would be in danger.
At first, the group thought that Xing was way out of boundsbut they quickly realized that Xing felt absolutely certain of what he was saying. Zori was quiet for the moment, just reflecting that maybe, just maybe, her skepticism over the relevance of the material in applied combinatorics was unjustified.
Nyt sinä Yksikään laskin ei ratkaise tätä, mutta sen osat ovat yhtä totta. Kokeile alla olevaa tai kirjoita omasi.
Vapaa tili lisää muistiinpanoja jokaiseen oppituntiin, muistiinpanoja siitä, mitä olet saanut päätökseen, ratkaistuja ongelmiasi yhdessä paikassa ja ohjaajaa, jolta voit kysyä tästä sivusta. Matematiikka on kaikille avoin, kirjautunut tai ei.
Rekisteröidy KirjautuminenSymbolit, joita käytetään täällä
Napauta symbolia koko määrittelyn, kuvan ja sen jokaisen kirjaimen osalta.
Kysymyksiä
Permutation or combination?
Ask whether order matters. A lock code is a permutation (order matters); a hand of cards is a combination (it does not).
What is a graph in this sense?
Dots (vertices) joined by lines (edges), not a plot. Road maps, social networks and molecules are graphs; questions like "is there a route" and "how few colours" are graph theory.
Osaa tästä sivusta on muokattu Keller & Trotter, Applied Combinatorics (CC BY-SA 4.0). Tässä on tiivistetty ja selitetty uudelleen, virheet ovat meidän.
Lisää Combinatorics & Graph Theory
The counting principlesPigeonhole principle and inclusion, exclusionBinomial coefficients and Pascal's triangleRecurrences and generating functionsGraphs: vertices, edges, degreesPaths, cycles, trees, Euler and HamiltonColouring and planar graphs