Eulerian circuit definition

Other articles where Eulerian circuit is discussed: graph theory: …vertex is known as an Eulerian circuit, and the graph is called an Eulerian graph. An Eulerian graph is connected and, in addition, all its vertices have even degree.

Eulerian circuit definition. A product xy x y is even iff at least one of x, y x, y is even. A graph has an eulerian cycle iff every vertex is of even degree. So take an odd-numbered vertex, e.g. 3. It will have an even product with all the even-numbered vertices, so it has 3 edges to even vertices. It will have an odd product with the odd vertices, so it does not have any ...

where e is the base of the natural logarithm, i is the imaginary unit, and cos and sin are the trigonometric functions cosine and sine respectively. This complex exponential function is sometimes denoted cis x ("cosine plus i sine"). The formula is still valid if x is a complex number, and so some authors refer to the more general complex version as Euler's …

A sequence of vertices \((x_0,x_1,…,x_t)\) is called a circuit when it satisfies only the first two of these conditions. Note that a sequence consisting of a single vertex is a circuit. Before proceeding to Euler's elegant characterization of eulerian graphs, let's use SageMath to generate some graphs that are and are not eulerian.May 4, 2022 · Euler's cycle or circuit theorem shows that a connected graph will have an Euler cycle or circuit if it has zero odd vertices. Euler's sum of degrees theorem shows that however many edges a ... where e is the base of the natural logarithm, i is the imaginary unit, and cos and sin are the trigonometric functions cosine and sine respectively. This complex exponential function is sometimes denoted cis x ("cosine plus i sine"). The formula is still valid if x is a complex number, and so some authors refer to the more general complex version as Euler's …Eulerian information concerns fields, i.e., properties like velocity, pressure and temperature that vary in time and space. Here are some examples: 1. Statements made in a weather forecast. “A cold air mass is moving in from the North.” (Lagrangian) “Here (your city), the temperature will decrease.” (Eulerian) 2. Ocean observations.An Euler path, in a graph or multigraph, is a walk through the graph which uses every edge exactly once. An Euler circuit is an Euler path which starts and stops at the same vertex. Our goal is to find a quick way to check whether a graph (or multigraph) has an Euler path or circuit.it contains an Euler cycle. It also makes the statement that only such graphs can have an Euler cycle. In other words, if some vertices have odd degree, the the graph cannot have an Euler cycle. Notice that this statement is about Euler cycles and not Euler paths; we will later explain when a graph can have an Euler path that is not an Euler ...Yes, a disconnected graph can have an Euler circuit. That's because an Euler circuit is only required to traverse every edge of the graph, it's not required to visit every vertex; so isolated vertices are not a problem. A graph is connected enough for an Euler circuit if all the edges belong to one and the same component.

In this section we are interested in simple circuits that pass through every single node in the graph; this type of circuit has a special name. A Hamiltonian arcuit of an undirected graph G = ( V, E) is a simple circuit that includes all the vertices of G. The graph in Figure 11.6 contains several Hamiltonian circuits—for example, 〈1, 4, 5 ... Euler's Circuit Theorem. The first theorem we will look at is called Euler's circuit theorem.This theorem states the following: 'If a graph's vertices all are even, then the graph has an Euler ...This was discussed in Video 22, and more information can be found here. One way to determine that a graph is Eulerian is to actually find an eulerian circuit, or determine that no such circuit exists. Another much simpler way was discussed in Video 22. Complete the function definition below for function eulerian.Theorem 13.2.1. If G is a graph with a Hamilton cycle, then for every S ⊂ V with S ≠ ∅, V, the graph G ∖ S has at most | S | connected components. Proof. Example 13.2.1. When a non-leaf is deleted from a path of length at least 2, the deletion of this single vertex leaves two connected components.Construction of Euler Circuits Let G be an Eulerian graph. Fleury’s Algorithm 1.Choose any vertex of G to start. 2.From that vertex pick an edge of G to traverse. Do not pick a bridge unless there is no other choice. 3.Darken that edge as a reminder that you cannot traverse it again. 4.Travel that edge to the next vertex. The definition of Euler path in the link is, however, wrong - the definition of Euler path is that it's a trail, not a path, which visits every edge exactly once. And in the definition of trail, we allow the vertices to repeat, so, in fact, every Euler circuit is also an Euler path.

Mar 24, 2023 · Cycle detection is a particular research field in graph theory. There are algorithms to detect cycles for both undirected and directed graphs. There are scenarios where cycles are especially undesired. An example is the use-wait graphs of concurrent systems. In such a case, cycles mean that exists a deadlock problem. contains an Euler circuit. Characteristic Theorem: We now give a characterization of eulerian graphs. Theorem 1.7 A digraph is eulerian if and only if it is connected and balanced. Proof: Suppose that Gis an Euler digraph and let C be an Euler directed circuit of G. Then G is connected since C traverses every vertex of G by the definition.An Euler path, in a graph or multigraph, is a walk through the graph which uses every edge exactly once. An Euler circuit is an Euler path which starts and stops at the same vertex. Our goal is to find a quick way to check whether a graph (or multigraph) has an Euler path or circuit.Circuits can be a great way to work out without any special equipment. To build your circuit, choose 3-4 exercises from each category liste. Circuits can be a great way to work out and reduce stress without any special equipment. Alternate ...It may look like one big switch with a bunch of smaller switches, but the circuit breaker panel in your home is a little more complicated than that. Read on to learn about the important role circuit breakers play in keeping you safe and how...Definition 6.1.2. A circuit that uses every edge in a connected graph, but never uses the same edge twice, is called an Eulerian circuit. A connected graph containing an Eulerian circuit is an Eulerian graph. Note: The definition of an Eulerian circuit implies that we can actually repeat vertices as long as each edge in the path is distinct.

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When \(\textbf{G}\) is eulerian, a sequence satisfying these three conditions is called an eulerian circuit. A sequence of vertices \((x_0,x_1,…,x_t)\) is …Definition 1 An eulerian circuit (or eulerian tour) is a circuit containing all of the edges and vertices of the (multi")graph. An eulerian trail is trail ...Prerequisite – Graph Theory Basics – Set 1 A graph is a structure amounting to a set of objects in which some pairs of the objects are in some sense “related”. The objects of the graph correspond to vertices and the relations between them correspond to edges.A graph is depicted diagrammatically as a set of dots depicting vertices connected …The Criterion for Euler Circuits I Suppose that a graph G has an Euler circuit C. I For every vertex v in G, each edge having v as an endpoint shows up exactly once in C. I The circuit C enters v the same number of times that it leaves v (say s times), so v has degree 2s. I That is, v must be an even vertex.

An Eulerian cycle, also called an Eulerian circuit, Euler circuit, Eulerian tour, or Euler tour, is a trail which starts and ends at the same graph vertex. In other words, it is a graph cycle which uses each graph edge exactly once. For technical reasons, Eulerian cycles are mathematically easier to study than are Hamiltonian cycles.All the planar representations of a graph split the plane in the same number of regions. Euler found out the number of regions in a planar graph as a function of the number of vertices and number of edges in the graph. Theorem – “Let be a connected simple planar graph with edges and vertices. Then the number of regions in the graph is …The models have been compared by simulation and the results reveal that the Eulerian circuit approach can achieve an improvement of 2% when comparing to the Hamiltonian circuit approach. ... By definition, a Hamiltonian cycle is a tour in a graph that visits all the vertices and edges of a graph once and starts and ends at the same vertex ...This circuit is called as Euler circuit[1]. II. HAMILTONIAN CYCLE. A. Definition and Problem. In the given figure, graph G (V, E), ...called an Euler trail in G if for every edge e of G, there is a unique i with 1 ≤ i < t so that e = x i x i+1. Definition A circuit (x 1, x 2, x 3, …, x t) in a graph G is called an Euler circuit if for every edge e in G, there is a unique i with 1 ≤ i ≤ t so that e = x i x i+1. Note that in this definition, we intend that x t x t+1 =x ... Eulerian circuit. Thus we must only have one Eulerian connected graph on 4 vertices. Indeed, here are all the connected graphs on four vertices. By the parity criterion we can see that only the one on the top right is Eulerian. Again, by the parity criterion, we can nd 4 connected graphs on 5 vertices below are Eulerian.The isomorphism graph can be described as a graph in which a single graph can have more than one form. That means two different graphs can have the same number of edges, vertices, and same edges connectivity. These types of graphs are known as isomorphism graphs. The example of an isomorphism graph is described as follows:Mathematically, ∑ deg(vi) = 2|E| ∑ d e g ( v i) = 2 | E |. where, |E| | E | stands for the number of edges in the graph (size of graph). The reasoning behind this result is quite simple. An edge is a link between two vertices. So each edge contributes exactly 2 2 to the degree sum. And hence, the degree sum must be twice the number of edges.

Now, if we increase the size of the graph by 10 times, it takes 100 times as long to find an Eulerian cycle: >>> from timeit import timeit >>> timeit (lambda:eulerian_cycle_1 (10**3), number=1) 0.08308156998828053 >>> timeit (lambda:eulerian_cycle_1 (10**4), number=1) 8.778133336978499. To make the runtime …

TOPICS. Algebra Applied Mathematics Calculus and Analysis Discrete Mathematics Foundations of Mathematics Geometry History and Terminology Number Theory Probability and Statistics Recreational Mathematics Topology Alphabetical Index New in MathWorldDefinition 1 An eulerian circuit (or eulerian tour) is a circuit containing all of the edges and vertices of the (multi")graph. An eulerian trail is trail ...Teahouse accommodation is available along the whole route, and with a compulsory guide, anybody with the correct permits can complete the circuit. STRADDLED BETWEEN THE ANNAPURNA MOUNTAINS and the Langtang Valley lies the comparatively undi...By definition a path graph cannot have an Eulerian circuit or a Hamiltonian cycle. A loop graph (consisting of one edge and one vertex) has both an Eulerian circuit and a Hamiltonian cycle. As above, there are examples where a graph might have one but not the other. The answer to your question is that there is no fundamental relationship ...Flow boiling occurs when a fluid circulates over a heated surface by external means such as a pump or due to the natural buoyancy effect [].Several flow patterns characterise such a flow field, and the transition between flow regimes dependent upon the channel geometry and thermophysical properties of the fluid [].A continuous flow of liquid …An Euler circuit is a circuit that uses every edge in a graph with no repeats. Being a circuit, it must start and end at the same vertex. Example The graph below has several possible Euler circuits. Here’s a couple, starting and ending at vertex A: ADEACEFCBA and AECABCFEDA. The second is shown in arrows. Euler Path. An Euler path is a path that uses every edge in a graph with no repeats. Being a path, it does not have to return to the starting vertex. Example. In the graph shown below, there are several Euler paths. One such path is CABDCB. The path is shown in arrows to the right, with the order of edges numbered.An Eulerian path through a graph is a path whose edge list contains each edge of the graph exactly once. If the path is a circuit, then it is called an Eulerian circuit. An Eulerian graph is a graph that possesses an Eulerian circuit.

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Mar 22, 2022 · Such a sequence of vertices is called a hamiltonian cycle. The first graph shown in Figure 5.16 both eulerian and hamiltonian. The second is hamiltonian but not eulerian. Figure 5.16. Eulerian and Hamiltonian Graphs. In Figure 5.17, we show a famous graph known as the Petersen graph. It is not hamiltonian. Eulerian information concerns fields, i.e., properties like velocity, pressure and temperature that vary in time and space. Here are some examples: 1. Statements made in a weather forecast. “A cold air mass is moving in from the North.” (Lagrangian) “Here (your city), the temperature will decrease.” (Eulerian) 2. Ocean observations.An Euler circuit is a circuit in a graph where each edge is traversed exactly once and that starts and ends at the same point. A graph with an Euler circuit in it is called Eulerian. All the ...1, then we call it a closed trail or a circuit (in this case, note that ‘ 3). A trail (resp., circuit) that uses all the edges of the graph is called an Eulerian trail (resp., Eulerian circuit). If a trail v 1v 2:::v ‘+1 satis es that v i 6= v j for any i 6= j, then it is called a path. A subgraph of G is a graph (V 0;E 0) such that V V and ... Aug 13, 2021 Eulerian Cycles and paths are by far one of the most influential concepts of graph theory in the world of mathematics and innovative technology. These circuits and paths were first discovered by Euler in 1736, therefore giving the name "Eulerian Cycles" and "Eulerian Paths."Construction of Euler Circuits Let G be an Eulerian graph. Fleury’s Algorithm 1.Choose any vertex of G to start. 2.From that vertex pick an edge of G to traverse. Do not pick a bridge unless there is no other choice. 3.Darken that edge as a reminder that you cannot traverse it again. 4.Travel that edge to the next vertex. All the planar representations of a graph split the plane in the same number of regions. Euler found out the number of regions in a planar graph as a function of the number of vertices and number of edges in the graph. Theorem – “Let be a connected simple planar graph with edges and vertices. Then the number of regions in the graph is …Definition 5.2.1 A walk in a graph is a sequence of vertices and edges, $$v_1,e_1,v_2,e_2,\ldots,v_k,e_k,v_{k+1}$$ such that the endpoints of edge $e_i$ are …1. @DeanP a cycle is just a special type of trail. A graph with a Euler cycle necessarily also has a Euler trail, the cycle being that trail. A graph is able to have a trail while not having a cycle. For trivial example, a path graph. A graph is able to have neither, for trivial example a disjoint union of cycles. – JMoravitz. ….

Using the graph shown above in Figure 6.4. 4, find the shortest route if the weights on the graph represent distance in miles. Recall the way to find out how many Hamilton circuits this complete graph has. The complete graph above has four vertices, so the number of Hamilton circuits is: (N – 1)! = (4 – 1)! = 3! = 3*2*1 = 6 Hamilton circuits. Lemma 1: If G is Eulerian, then every node in G has even degree. Proof: Let G = (V, E) be an Eulerian graph and let C be an Eulerian circuit in G.Fix any node v.If we trace …A product xy x y is even iff at least one of x, y x, y is even. A graph has an eulerian cycle iff every vertex is of even degree. So take an odd-numbered vertex, e.g. 3. It will have an even product with all the even-numbered vertices, so it has 3 edges to even vertices. It will have an odd product with the odd vertices, so it does not have any ...Definition 5.2.1 A walk in a graph is a sequence of vertices and edges, v1,e1,v2,e2, …,vk,ek,vk+1 v 1, e 1, v 2, e 2, …, v k, e k, v k + 1. such that the endpoints of edge ei e i are vi v i and vi+1 v i + 1. In general, the edges and vertices may appear in the sequence more than once. If v1 =vk+1 v 1 = v k + 1, the walk is a closed walk or ...called an Euler trail in G if for every edge e of G, there is a unique i with 1 ≤ i < t so that e = x i x i+1. Definition A circuit (x 1, x 2, x 3, …, x t) in a graph G is called an Euler circuit if for every edge e in G, there is a unique i with 1 ≤ i ≤ t so that e = x i x i+1. Note that in this definition, we intend that x t x t+1 =x ...An Euler circuit is a type of circuit that uses every edge in a graph with no repeats. Being a circuit, it must start and end at the same vertex. Example15.8.Mathematically, ∑ deg(vi) = 2|E| ∑ d e g ( v i) = 2 | E |. where, |E| | E | stands for the number of edges in the graph (size of graph). The reasoning behind this result is quite simple. An edge is a link between two vertices. So each edge contributes exactly 2 2 to the degree sum. And hence, the degree sum must be twice the number of edges.62 Eulerian andHamiltonianGraphs The followingcharacterisation of Eulerian graphs is due to Veblen [254]. Theorem 3.2 A connected graph G is Eulerian if and onlyif its edge set can be decom-posedinto cycles. Proof Let G(V, E) be a connected graph and let be decomposed into cycles. If k of these cycles are incident at a particular vertex v, then ...Now, if we increase the size of the graph by 10 times, it takes 100 times as long to find an Eulerian cycle: >>> from timeit import timeit >>> timeit (lambda:eulerian_cycle_1 (10**3), number=1) 0.08308156998828053 >>> timeit (lambda:eulerian_cycle_1 (10**4), number=1) 8.778133336978499. To make the runtime … Eulerian circuit definition, called an Euler trail in G if for every edge e of G, there is a unique i with 1 ≤ i < t so that e = x i x i+1. Definition A circuit (x 1, x 2, x 3, …, x t) in a graph G is called an Euler circuit if for every edge e in G, there is a unique i with 1 ≤ i ≤ t so that e = x i x i+1. Note that in this definition, we intend that x t x t+1 =x ..., Jun 26, 2023 · Circuit is a closed trail. These can have repeated vertices only. 4. Path – It is a trail in which neither vertices nor edges are repeated i.e. if we traverse a graph such that we do not repeat a vertex and nor we repeat an edge. As path is also a trail, thus it is also an open walk. Another definition for path is a walk with no repeated vertex. , A Hamiltonian cycle, also called a Hamiltonian circuit, Hamilton cycle, or Hamilton circuit, is a graph cycle (i.e., closed loop) through a graph that visits each node exactly once (Skiena 1990, p. 196). A graph possessing a Hamiltonian cycle is said to be a Hamiltonian graph. By convention, the singleton graph K_1 is considered to be …, A Hamiltonian path, much like its counterpart, the Hamiltonian circuit, represents a component of graph theory. In graph theory, a graph is a visual representation of data that is characterized by ..., A sequence of vertices \((x_0,x_1,…,x_t)\) is called a circuit when it satisfies only the first two of these conditions. Note that a sequence consisting of a single vertex is a circuit. Before proceeding to Euler's elegant characterization of eulerian graphs, let's use SageMath to generate some graphs that are and are not eulerian., Definition 9.4.4. Eulerian Paths, Circuits, Graphs. An Eulerian path through a graph is a path whose edge list contains each edge of the graph exactly once. If the path is a circuit, then it is called an Eulerian circuit. An Eulerian graph is a graph that possesses an Eulerian circuit. 🔗., it contains an Euler cycle. It also makes the statement that only such graphs can have an Euler cycle. In other words, if some vertices have odd degree, the the graph cannot have an Euler cycle. Notice that this statement is about Euler cycles and not Euler paths; we will later explain when a graph can have an Euler path that is not an Euler ... , An Eulerian circuit is a closed trail that contains every edge of a graph, and an Eulerian trail is an open trail that contains all the edges of a graph but doesn’t end in the same start vertex. This article also explains the Königsberg Bridge Problem and how it’s impossible to find a trail on it. Finally there are two implementations in ..., 1. @DeanP a cycle is just a special type of trail. A graph with a Euler cycle necessarily also has a Euler trail, the cycle being that trail. A graph is able to have a trail while not having a cycle. For trivial example, a path graph. A graph is able to have neither, for trivial example a disjoint union of cycles. – JMoravitz., Eulerian Circuit. An Eulerian path that starts and ends at the same vertex,or A circuit that includes all vertices and edges of a graph G,or A circuit passing through every edge just …, Euler Circuit Definition. An Euler circuit can easily be found using the model of a graph. A graph is a collection of objects and a list of the relationships between pairs of those objects ..., Sep 29, 2021 · An Euler path, in a graph or multigraph, is a walk through the graph which uses every edge exactly once. An Euler circuit is an Euler path which starts and stops at the same vertex. Our goal is to find a quick way to check whether a graph (or multigraph) has an Euler path or circuit. , Sep 29, 2021 · An Euler path, in a graph or multigraph, is a walk through the graph which uses every edge exactly once. An Euler circuit is an Euler path which starts and stops at the same vertex. Our goal is to find a quick way to check whether a graph (or multigraph) has an Euler path or circuit. , Using the graph shown above in Figure 6.4. 4, find the shortest route if the weights on the graph represent distance in miles. Recall the way to find out how many Hamilton circuits this complete graph has. The complete graph above has four vertices, so the number of Hamilton circuits is: (N – 1)! = (4 – 1)! = 3! = 3*2*1 = 6 Hamilton circuits. , This is because the Euler circuit cannot repeat the edges. So when we follow the path (A, F, E, G, C, D, B, A), in this process, many edges are not covered, i.e., F to G, A to E, e to D, and B to C, which violates the definition of Euler circuit. So the above graph does not contain an Euler circuit. Hence, it is not an Euler Graph., Properties. If n = 1, then the condition for any two vertices forming an edge holds vacuously, and hence all the vertices are connected, forming a total of m 2 edges.; Each vertex has exactly m incoming and m outgoing edges.; Each n-dimensional De Bruijn graph is the line digraph of the (n – 1)-dimensional De Bruijn graph with the same set of symbols.; Each …, Construction of Euler Circuits Let G be an Eulerian graph. Fleury’s Algorithm 1.Choose any vertex of G to start. 2.From that vertex pick an edge of G to traverse. Do not pick a bridge unless there is no other choice. 3.Darken that edge as a reminder that you cannot traverse it again. 4.Travel that edge to the next vertex., A compatible Eulerian circuit of an Eulerian graph G with a generalized transition system F (G) is defined as an Eulerian circuit in which no two consecutive edges form a transition defined by F (G). In this paper, we further introduce the concept of weakly generalized transition system which is an extension of the generalized transition system ..., The breakers in your home stop the electrical current and keep electrical circuits and wiring from overloading if something goes wrong in the electrical system. Replacing a breaker is an easy step-by-step process, according to Electrical-On..., Two strategies for genome assembly: from Hamiltonian cycles to Eulerian cycles (a) A simplified example of a small circular genome.(b) In traditional Sanger sequencing algorithms, reads were represented as nodes in a graph, and edges represented alignments between reads.Walking along a Hamiltonian cycle by following …, Feb 8, 2018 · Euler circuit. An Euler circuit is a connected graph such that starting at a vertex a a, one can traverse along every edge of the graph once to each of the other vertices and return to vertex a a. In other words, an Euler circuit is an Euler path that is a circuit. , If a graph has an Euler circuit, that will always be the best solution to a Chinese postman problem. Let’s determine if the multigraph of the course has an Euler circuit by looking at the degrees of the vertices in Figure 12.130. Since the degrees of the vertices are all even, and the graph is connected, the graph is Eulerian., In graph theory, a planar graph is a graph that can be embedded in the plane, i.e., it can be drawn on the plane in such a way that its edges intersect only at their endpoints.In other words, it can be drawn in such a way that no edges cross each other. Such a drawing is called a plane graph or planar embedding of the graph.A plane graph can be defined as …, be an Euler Circuit and there cannot be an Euler Path. It is impossible to cross all bridges exactly once, regardless of starting and ending points. EULER'S THEOREM 1 If a graph has any vertices of odd degree, then it cannot have an Euler Circuit. If a graph is connected and every vertex has even degree, then it has at least one Euler Circuit. , The isomorphism graph can be described as a graph in which a single graph can have more than one form. That means two different graphs can have the same number of edges, vertices, and same edges connectivity. These types of graphs are known as isomorphism graphs. The example of an isomorphism graph is described as follows:, In this post, an algorithm to print an Eulerian trail or circuit is discussed. Following is Fleury’s Algorithm for printing the Eulerian trail or cycle. Make sure the graph has either 0 or 2 odd vertices. If there are 0 odd vertices, start anywhere. If there are 2 odd vertices, start at one of them. Follow edges one at a time., An Eulerian graph is a graph that contains an Euler circuit. In other words, the graph is either only isolated points or contains isolated points as well as exactly one group of connected vertices ..., Jun 16, 2020 · The Euler Circuit is a special type of Euler path. When the starting vertex of the Euler path is also connected with the ending vertex of that path, then it is called the Euler Circuit. To detect the path and circuit, we have to follow these conditions −. The graph must be connected. When exactly two vertices have odd degree, it is a Euler Path. , Apr 18, 2023 · An Eulerian circuit is a closed trail that contains every edge of a graph, and an Eulerian trail is an open trail that contains all the edges of a graph but doesn’t end in the same start vertex. This article also explains the Königsberg Bridge Problem and how it’s impossible to find a trail on it. Finally there are two implementations in ... , In graph theory, an Eulerian trail is a trail in a finite graph that visits every edge exactly once . Similarly, an Eulerian circuit or Eulerian cycle is an Eulerian trail that starts and ends on the same vertex. They were first discussed by Leonhard Euler while solving the famous Seven Bridges of Königsberg problem in 1736. The problem can be stated mathematically like this: , 31/05/2015 ... Unless they are using non standard definitions then "Euler path is when two of its vertices are of odd degree" this isn't technically correct., Analysts have been eager to weigh in on the Technology sector with new ratings on Adobe (ADBE – Research Report), Jabil Circuit (JBL – Research... Analysts have been eager to weigh in on the Technology sector with new ratings on Adobe (ADBE..., Steps to Find an Euler Circuit in an Eulerian Graph. Step 1 - Find a circuit beginning and ending at any point on the graph. If the circuit crosses every edges of the graph, the circuit you found is an Euler circuit. If not, move on to step 2. Step 2 - Beginning at a vertex on a circuit you already found, find a circuit that only includes edges ...