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The perfect matching counting problem was the first counting problem corresponding to an easy P problem shown to be # P-complete, in a 1979 paper by Leslie Valiant which also defined the classes # P and # P-complete for the first time.
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perfect and matching
The same observation can be made for the perfect matching problem.
It was known before that the decision problem " Is there a perfect matching for a given bipartite graph?
The Christofides algorithm follows a similar outline but combines the minimum spanning tree with a solution of another problem, minimum-weight perfect matching.
This is the concept of ' exact ' or ' perfect ' matching to the translation memory.
Pulse-amplitude modulation LED drivers are able to synchronize pulses across multiple LED channels to enable perfect colour matching.
Recognizing the paramount importance of the sacred shield descended from the skies, King Numa had eleven matching shields made, so perfect that no one, even Numa, could distinguish the original any longer.
Because it was the perfect, perfect, perfect matching of personalities and gifts.
The minor can be formed by contracting the edges of a perfect matching, for instance the five short edges in the first picture.
* is cubic, has domination number 3, and has a perfect matching and a 2-factor.
If the weight of a perfect matching that matches to is defined to be the product of the weights of the edges in the matching, then
Closely related to the complete bipartite graphs are the crown graphs, formed from complete bipartite graphs by removing the edges of a perfect matching.
A perfect matching describes a way of simultaneously satisfying all job-seekers and filling all jobs ; the marriage theorem provides a characterization of the bipartite graphs which allow perfect matchings.
This simple matching network consisting of a single element will usually only achieve a perfect match at a single frequency.
In general, it is not theoretically possible to achieve perfect impedance matching at all frequencies with a network of discrete components.
Outerplanar graphs were first studied and named by, in connection with the problem of determining the planarity of graphs formed by using a perfect matching to connect two copies of a base graph ( for instance, many of the generalized Petersen graphs are formed in this way from two copies of a cycle graph ).
The Turán graph T ( 2n, n ) can be formed by removing a perfect matching from a complete graph K < sub > 2n </ sub >.
A perfect matching ( a. k. a. 1-factor ) is a matching which matches all vertices of the graph.
Figure ( b ) above is an example of a perfect matching.
Every perfect matching is maximum and hence maximal.
perfect and counting
The problem of counting the number of perfect matchings ( or in directed graphs: the number of vertex cycle covers ) is known to be equivalent to the problem of the computation of the permanent of a matrix.
85 is the product of two prime numbers ( 5 and 17 ), and is therefore a biprime ; specifically, the 24th biprime not counting perfect squares.
* Choice Uncirculated / Crisp Choice Uncirculated-Just less than perfect, tiny foxing, faint counting smudges, or slightly off-center margins
perfect and problem
Acquiring a repertoire from the Laboratory library was no problem to one trained to perfect recall.
The discovery of CP violation helped to shed light on this problem by showing that this symmetry, originally thought to be perfect, was only approximate.
Nevertheless, Wells has this very same Time Traveller speak in terms unusual for socialist thought, referring as " perfect " and with no social problem unsolved, to an imagined world of stark class division between the rich assured of their wealth and comfort, and the rest of humanity assigned to lifelong toil: Once, life and property must have reached almost absolute safety.
No doubt in that perfect world there had been no unemployed problem, no social question left unsolved.
Proposing a solution to the theological problem of reconciling the doctrine with that of universal redemption in Christ, he argued that Mary's immaculate conception did not remove her from redemption by Christ ; rather it was the result of a more perfect redemption granted her because of her special role in salvation history.
One solution to avoid this problem is to use a protocol that has perfect forward secrecy.
Thus the Augustinian theodicist would argue that the problem of evil and suffering is void because God did not create evil ; it was man who chose to deviate from the path of perfect goodness.
Due to an increase in many businesses requiring their employees to travel, singles, often young professionals, find online dating websites to be the perfect answer to their " problem ", states Brym and Lenton.
It reconciles the " problem " of the Trinity ( or at least Jesus ) by holding that the Son was not co-eternal with the Father, and that Jesus Christ was essentially granted godhood ( adopted ) for the plans of God and for his own perfect life and works.
Pillai's conjecture concerns a general difference of perfect powers: it is an open problem initially proposed by S. S. Pillai, who conjectured that the gaps in the sequence of perfect powers tend to infinity.
The routing problem is equivalent to the travelling salesman problem, which is NP complete, and therefore not amenable to a perfect solution on a reasonable time scale.
One problem noted with this approach is that there seems to be no fixed basis on deciding what God is not, unless the Divine is understood as an abstract experience of full aliveness unique to each individual consciousness, and universally, the perfect goodness applicable to the whole field of reality.
This seemed like the perfect solution to her problem to reclaim her husband's love from him Iole, the foreign concubine.
Because of simplifications introduced along every step of the way, the corrections are never perfect, but even one cycle of corrections often provides a remarkably better approximate solution to the real problem.
The problem is that critics have been unable to agree on how to reconcile his perfect “ saintliness ” with his obvious adultery with King Arthur ’ s Guinevere.
perfect and was
the calf was magnificent, the ankle perfect.
But she was afraid the First Lady would not understand, because Rob Roy was a perfect angel with the First Family.
It seemed, indeed, that their house was not so much a home, but rather a perfect stage set, and that they were actors who had been handed fat roles in a successful play, and had talent enough to fill the roles competently, with nice understatement.
That the perfect continuity was composed from the joblot of memory impressions in the professor's brain, or 2.
As he went out he told Freddie the dinner was perfect, and when he got his hat and coat from Nancy Parks and put a fifty-cent piece in the slot, he told her to be sure that it went toward her dowry.
Here was a perfect place to lie down and make believe.
Hadn't Linda been a perfect wife to Bobbie, who was the least bit of a disappointment all these years??
Thus, the masculine animate infinitive dabhumaksanigalu'ahai, meaning to live, was, in the perfect tense, ksu'u'peli'afo, and, in the future, mai'teipa.
Francois Boucher was the 18th century painter and engraver whose works are regarded as the perfect expression of French taste in the Rococo period.
There was an ongoing tradition of allowing anagrams to be " perfect " if the letters were all used once, but allowing for these interchanges.
He hoped to perfect the human spirit and, to that end, advocated a vegan diet before the term was coined.
Their goal was to regain access to Eden by finding the correct formula for perfect living, following specific rules governing agriculture, diet, and reproduction.
The episode at Blake Hall was so traumatic that she reproduced it in almost perfect detail in her novel, Agnes Grey.
It was here he was to perfect himself by a study of the most splendid relics of antiquity, and to put his talents to the severest test by a competition with the living masters of the art.
Ben Adret, while reluctant to interfere in the affairs of other congregations, was in perfect accord with Abba Mari as to the danger of the new rationalistic systems, and advised him to organize the conservative forces in defense of the Law.
Zeus needed an elite army and at first thought that Aegina, which at the time did not have any villagers, was the perfect place.
The Aleut baidarka resembled that of an Eskimo Kayak, however, it was designed to be much more aerodynamically fast which was perfect for sea hunting.
The Stadium was the scene Lou Gehrig's Farewell Speech in 1939, Don Larsen's perfect game in the 1956 World Series, Roger Maris ' record breaking 61st home run in 1961, and Reggie Jackson's 3 home runs to clinch Game 6 of the 1977 World Series.
Both Bucer and Peter Martyr wrote detailed proposals for modification ; Bucer's Censura ran to 28 chapters which influenced Cranmer significantly though he did not follow them slavishly and the new book was duly produced in 1552, making " fully perfect " what was already implicit.
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