Difference between revisions of "TADM2E 6.17"

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a) No, Look at the graph on page 196 for a counter example.
 
a) No, Look at the graph on page 196 for a counter example.
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No to both.  A counterexample to both is a four node, four edge graph connected in a square:
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*Edge 1 - A:B, weight 1
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*Edge 2 - B:C, weight 7
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*Edge 3 - C:D, weight 2
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*Edge 4 - D:A, weight 8
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The MST is A:B:C:D, and edge 4 is never included.  The path from A to D through the MST is 10, but the direct path through edge 4 is weight 8.

Latest revision as of 19:12, 23 April 2015

a) No, Look at the graph on page 196 for a counter example.


No to both. A counterexample to both is a four node, four edge graph connected in a square:

  • Edge 1 - A:B, weight 1
  • Edge 2 - B:C, weight 7
  • Edge 3 - C:D, weight 2
  • Edge 4 - D:A, weight 8

The MST is A:B:C:D, and edge 4 is never included. The path from A to D through the MST is 10, but the direct path through edge 4 is weight 8.