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G190852562
Posts: 162
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Posted 03:13 Dec 07, 2014 |
5. The wiki page presents pseudo-code for Karger's algorithm. For a graph has n nodes and m edges what is the computational complexity of Karger's algorithm in big-O terms? O(n + m) |
yxu22
Posts: 25
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Posted 09:18 Dec 07, 2014 |
Each merge would only reduce the number of edges by 1 not reduce half. So the complexity is O( n * m) |
G190852562
Posts: 162
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Posted 14:28 Dec 07, 2014 |
Okay, but wouldn't reducing the edges by 1 be a constant process? Why is it O(n * m) instead of O(n)? |
yxu22
Posts: 25
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Posted 14:35 Dec 07, 2014 |
Because we need to merge until only two combined component left. So in the worst case (there would be only 1 cross edge), we need to merge m-1 times (initially we have m edges, we merge m-1 times, then we have 1 cross edge left.) So generally speaking, running time is O(n * m ) |
G190852562
Posts: 162
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Posted 14:41 Dec 07, 2014 |
So for each iteration n, there is a merge that occurs yielding us O(n * m) complexity? |
yxu22
Posts: 25
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Posted 14:43 Dec 07, 2014 |
Right |