Interactive end-of-chapter exercises


Dijkstra's Link State Algorithm - Advanced

Consider the incomplete 6-node network shown below, with the given link costs.

Consider the completed table below, which calculates the shortest distance to all nodes from U:
================================================
|    Node     |    Shortest distance from U    |    Previous Node   |
================================================
       U                                0                                     n/a   
       V                                3                                     U   
       W                               4                                     V   
       X                                6                                     U   
       Y                                7                                     W   
       Z                                8                                     Y   
================================================



Question List


1. For link X, what is the cost associated with this link? If the answer can't be determined given the information, respond with 'n/a'

2. For link Y, what is the cost associated with this link? If the answer can't be determined given the information, respond with 'n/a'




Solution


1. Because the link is never used, we cannot determine the value of X, so the answer is n/a.

2. The prior node in the path to Z is Y, and we know the shortest distance of both Z (8) and Y (7), so 8 - 7 = 1 which is Y.



That's incorrect

That's correct

The answer was: n/a

Question 1 of 2

The answer was: 1

Question 2 of 2

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