Let G be a weighted undirected graph and e be an edge with maximum wei...
Background : Given a connected and undirected graph, a spanning tree of that graph is a subgraph that is a tree and connects all the vertices together.
- A spanning tree has exactly V - 1 edges.
- A single graph can have many different spanning trees. A minimum spanning tree (MST) or minimum weight spanning tree for a weighted, connected and undirected graph is a spanning tree with weight less than or equal to the weight of every other spanning tree. The weight of a spanning tree is the sum of weights given to each edge of the spanning tree.
- There can be more that one possible spanning trees of a graph. For example, the graph in this question has 6 possible spanning trees.
- MST has lightest edge of every cutset. Remember Prim's algorithm which basically picks the lightest edge from every cutset.
Choices of this question :
a) There exists a cutset in G having all edges of maximum weight : This is correct. If there is a heaviest edge in MST, then there exist a cut with all edges with weight equal to heavies edge. See point 4 discussed in above background.
b) There exists a cycle in G having all edges of maximum weight : Not always TRUE. The cutset of heaviest edge may contain only one edge. In fact there may be overall one edge of heavies weight which is part of MST (Consider a graph with two components which are connected by only one edge and this edge is the heavies)
c) Edge e cannot be contained in a cycle. Not Always True. The curset may form cycle with other edges. d) All edges in G have the same weight Not always True. As discussed in option b, there can be only one edge of heaviest weight.
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Let G be a weighted undirected graph and e be an edge with maximum wei...
Background : Given a connected and undirected graph, a spanning tree of that graph is a subgraph that is a tree and connects all the vertices together.
- A spanning tree has exactly V - 1 edges.
- A single graph can have many different spanning trees. A minimum spanning tree (MST) or minimum weight spanning tree for a weighted, connected and undirected graph is a spanning tree with weight less than or equal to the weight of every other spanning tree. The weight of a spanning tree is the sum of weights given to each edge of the spanning tree.
- There can be more that one possible spanning trees of a graph. For example, the graph in this question has 6 possible spanning trees.
- MST has lightest edge of every cutset. Remember Prim's algorithm which basically picks the lightest edge from every cutset.
Choices of this question :
a) There exists a cutset in G having all edges of maximum weight : This is correct. If there is a heaviest edge in MST, then there exist a cut with all edges with weight equal to heavies edge. See point 4 discussed in above background.
b) There exists a cycle in G having all edges of maximum weight : Not always TRUE. The cutset of heaviest edge may contain only one edge. In fact there may be overall one edge of heavies weight which is part of MST (Consider a graph with two components which are connected by only one edge and this edge is the heavies)
c) Edge e cannot be contained in a cycle. Not Always True. The curset may form cycle with other edges. d) All edges in G have the same weight Not always True. As discussed in option b, there can be only one edge of heaviest weight.
Let G be a weighted undirected graph and e be an edge with maximum wei...
Explanation:
Minimum Weight Spanning Tree:
- A minimum weight spanning tree is a subgraph that is a tree which connects all the vertices in a graph with the minimum possible total edge weight.
Maximum Weight Edge:
- The edge with the maximum weight in a graph is denoted as 'e'.
Statement:
- The statement says that if there is a minimum weight spanning tree containing the edge 'e', then there exists a cutset in the graph having all edges of maximum weight.
Explanation:
- When the minimum weight spanning tree contains the edge with the maximum weight, it means that all other edges in the tree have weights less than 'e'.
- To disconnect the graph into two components, a cutset needs to be identified, and in this case, the cutset will consist of all edges of maximum weight, including the edge 'e'.
- This guarantees that removing these edges will disconnect the graph and separate it into two components.
Conclusion:
- Therefore, the correct statement is option 'A' which states that there exists a cutset in the graph having all edges of maximum weight when a minimum weight spanning tree containing the edge 'e' exists.
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