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What is hashCode used for? Is it unique?
...r is based on the
System.Collections.IEqualityComparer interface.
Basically, hash codes exist to make hashtables possible.
Two equal objects are guaranteed to have equal hashcodes.
Two unequal objects are not guaranteed to have unequal hashcodes (that's called a collision).
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Why do I need to explicitly push a new branch?
... did git push my branch was not uploaded to the repository. I had to actually do: git push -u origin --all .
Why is this? Isn't a branch a new change to be pushed by default? Why do I need to run the second command?
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How to tell where a header file is included from?
How can I tell where g++ was able to find an include file? Basically if I
4 Answers
4...
R - Concatenate two dataframes?
...2 data frames, you can use Reduce(rbind, list_of_data_frames) to mash them all together!
– Yourpalal
Aug 13 '15 at 21:12
1
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How to change past commit to include a missed file?
...s that the case even if I am the only user of the remote repo? Wouldn't it allow me to do git push -f if I am sure the upstream didn't change?
– kolrie
Jan 16 '13 at 22:48
1
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Effect of NOLOCK hint in SELECT statements
...l complete faster than a normal select.
2) Yes, a select with NOLOCK will allow other queries against the effected table to complete faster than a normal select.
Why would this be?
NOLOCK typically (depending on your DB engine) means give me your data, and I don't care what state it is in, and d...
Big O of JavaScript arrays
...pending - Amortized O(1) (sometimes resizing the hashtable is required; usually only insertion is required)
Prepending - O(n) via unshift, since it requires reassigning all the indexes
Insertion - Amortized O(1) if the value does not exist. O(n) if you want to shift existing values (Eg, using splice...
How to call Base Class's __init__ method from the child class? [duplicate]
... If you pass BaseClass to super, it'll skip over BaseClass and call object.__init__, which is almost certainly not what you want.
– abarnert
Oct 6 '13 at 7:29
1
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Abstract methods in Python [duplicate]
...what a metaclass is, don't worry about it. :-)
– kindall
Dec 8 '10 at 0:15
1
The linked tutorial ...
What is the formal difference in Scala between braces and parentheses, and when should they be used?
...ut this, but I gave up in the end, as the rules are somewhat diffuse. Basically, you’ll have to get the hang of it.
Perhaps it is best to concentrate on where curly braces and parenthesis can be used interchangeably: when passing parameters to method calls. You may replace parenthesis with curly b...