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Let G be any connected, weighted, undirected graph. I. G has a unique minimum spanning tree, if no two edges of G have the same weight. II. G has a unique minimum spanning tree, if, for every cut of G, there is a unique minimum-weight edge crossing the cut. Which of the above two statements is/are TRUE?

Let G be any connected, weighted, undirected graph. I. G has a unique minimum spanning tree, if no two edges of G have the same weight. II. G has a unique minimum spanning tree, if, for every cut of G, there is a unique minimum-weight edge crossing the cut. Which of the above two statements is/are TRUE? Correct Answer Both I and II

Concept:

A minimum spanning tree (MST) or minimum weight spanning tree is a subset of the edges(V – 1 ) of a connected, edge-weighted undirected graph G(V, E) that connects all the vertices together, without any cycles and with the minimum possible total edge weight.

Example:

Graph G(V, E)

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G(V, V – 1) → minimum spanning tree

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If edge weights are distinct then there exist unique MST.

Hence option 1 is correct

Theorem:

If for every cut of a graph there is a unique light edge crossing the cut then the graph has a unique minimum spanning tree, but converse may not be true.

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