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Why is the time complexity of both DFS and BFS O( V + E )
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If in an adjacency list, each vertex is connected to all other vertices the would the complexity be equivalent to O(V+E)=O(V+V^2)=O(V^2). E=V^2 because the most number of edges = V^2.
– Max
Feb 24 '17 at 8:29
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Rails find_or_create_by more than one attribute?
There is a handy dynamic attribute in active-record called find_or_create_by:
5 Answers
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Rails 4 LIKE query - ActiveRecord adds quotes
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Should really be easy to create a func to do this dynamically with a list of attributes
– cevaris
Feb 28 '16 at 17:16
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How to echo shell commands as they are executed
In a shell script, how do I echo all shell commands called and expand any variable names?
13 Answers
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How do I remove version tracking from a project cloned from git?
I want to remove all version tracking from a project's directory.
9 Answers
9
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What's the u prefix in a Python string?
... Mar 17 '10 at 18:45
Stefan KendallStefan Kendall
59.9k6161 gold badges228228 silver badges387387 bronze badges
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How do I create a unique ID in Java? [duplicate]
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It's not all that human readable tho...
– pjp
Sep 7 '09 at 14:56
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What's the difference between RANK() and DENSE_RANK() functions in oracle?
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with q as (
select 10 deptno, 'rrr' empname, 10000.00 sal from dual union all
select 11, 'nnn', 20000.00 from dual union all
select 11, 'mmm', 5000.00 from dual union all
select 12, 'kkk', 30000 from dual union all
select 10, 'fff', 40000 from dual union all
select 10, 'ddd', 40000 from dual union ...
MPICH vs OpenMPI
...xtensive optimizations that make it the preferred implementation in nearly all cases.
Feature Support from the Latest MPI Standard
An orthogonal axis to hardware/platform support is coverage of the MPI standard. Here MPICH is usually far and away superior. MPICH has been the first implementation...
How does Apple find dates, times and addresses in emails?
...ay be wrong). On the other hand I'd except the naiive approach of encoding all common formats to perform way better (possibly 0.99+ given that the most frequent formats will never be missed) and to be faster to implement + at runtime.
– b.buchhold
Feb 25 '12 at...