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Discussion
Over coffee, today's conversation was enthusiastic and heated at times.
Discussion
Over coffee, today's conversation was enthusiastic and heated at times. Zori got things off with a blast I don't think graphs are of any use at all but she wasn't even able to finish the sentence before Yolanda uncharacteristically interrupted her with You're off base on this one. I see lots of ways graphs can be used to model real world problems. The professor actually showed us examples back in our first class. But now that we're talking in more depth about graphs, things are even clearer. Bob added, These eulerian and hamiltonian cycle problems are certain to have applications in network routing problems. Xing reinforced Bob with Absolutely. There are important questions in network integrity and information exchange that are very much the same as these basic problems. Alice piled on Even the notion of chromatic number clearly has practical applications. By this time, Zori realized her position was indefensible but she was reluctant to admit it. She offered only a Whatever.
Things quieted down a bit and Dave said Finding a hamiltonian cycle can't be all that hard, if someone guarantees that there is one. This extra information must be of value in the search. Xing added Maybe so. It seems natural that it should be easier to find something if you know it's there. Alice asked Does the same thing hold for chromatic number? Bob didn't understand her question Huh? Alice continued, this time being careful not to even look Bob's way I mean if someone tells you that a graph is \(3\)-colorable, does that help you to find a coloring using only three colors? Dave said Seems reasonable to me.
After a brief pause, Carlos offered I don't think this extra knowledge is of any help. I think these problems are pretty hard, regardless. They went back and forth for a while, but in the end, the only thing that was completely clear is that graphs and their properties had captured their attention, at least for now.
Haddaad Ma jiro xisaabis oo ku nool midkan, laakiin qaybaha ka mid ah waa la xisaabi karaa. Ku raaxayso mid ka hooseeya, ama ku qor adiga kuu gaar ah.
A xisaab bilaash ah oo ku daray qoraalada waxbarasho kasta, diiwaanka waxa aad dhamaatay, dhibaatooyinka aad xal u tahay meel kaliya, iyo macallinka aad weydiisan kartaa oo ku saabsan bogga. Xisaabta oo keliya waa u furan yahay qof kasta, la diiwaan geliyey ama aan.
Ku soo biir Ku soo galCalaamadaha la isticmaalay halkan
Taab calaamad kasta oo loogu talagalay qeexidda buuxda, sawir, iyo waxa xarfaha oo dhan ka mid ah ka dhigan tahay.
Su'aalaha dadku waydiiyaan
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.
Qaybaha ee boggaan waxaa la beddelay ka Keller & Trotter, Applied Combinatorics (CC BY-SA 4.0). Condensed iyo dib-oo halkan lagu sharaxay; khaladaadka waa inoo.
In ka badan 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