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 W:
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|    Node     |    Shortest distance from W    |    Previous Node   |
================================================
       W                               0                                     n/a   
       X                                2                                     W   
       Y                                2                                     W   
       V                                4                                     X   
       U                                5                                     X   
       Z                                7                                     W   
================================================



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. The prior node in the path to Y is W, and we know the shortest distance of both Y (2) and W (0), so 2 - 0 = 2 which is X.

2. The prior node in the path to V is X, and we know the shortest distance of both V (4) and X (2), so 4 - 2 = 2 which is Y.



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The answer was: 2

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The answer was: 2

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