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What does “javascript:void(0)” mean?
I've seen such href s many times, but I don't know what exactly that means.
14 Answers
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Find a pair of elements from an array whose sum equals a given number
...y element into a hash table (without sorting). This takes O(n) as constant time insertion.
Then for every x,
we can just look up its complement, T-x, which is O(1).
Overall the run time of this approach is O(n).
You can refer more here.Thanks.
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How to get a password from a shell script without echoing
...s] [-a array] [-d delim] [-i text] [-n nchars] [-N nchars] [-p prompt] [-t timeout] [-u fd] [name ...]
Read a line from the standard input and split it into fields.
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-p prompt output the string PROMPT without a trailing newline before
attempting to read
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-s d...
How to find all occurrences of an element in a list?
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This was a long time ago, I probably used timeit.timeit with randomly generated lists. That's an important point though, and I suppose that may be why you ask. At the time it didn't occur to me, but the speed gains are only true if the resul...
How to define hash tables in Bash?
...re to another list of keys, instead of O(n) with proper hashmaps (constant time lookup, O(1) for a single key).
– CodeManX
Aug 23 '15 at 19:01
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TortoiseGit save user authentication / credentials
...edential Manager, the successor of git-credential-winstore)
For the first time you sync you are asked for user and password, you enter them and they will be saved to Windows credential store. It won't ask for user or password the next time you sync.
To use: Right click → TortoiseGit → Settings...
What is the difference between dict.items() and dict.iteritems() in Python2?
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@RubenGeert Most of the time, it doesn't matter. For really large dicts it might be preferable.
– Keith
Nov 12 '18 at 3:44
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What is your favorite C programming trick? [closed]
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I sometimes extend this to: const struct something zero_something = { 0 }; and then I can reset a variable on the fly with struct something X = zero_something; or part-way through a routine I can use 'X = zero_something;'. The onl...
Combine two columns of text in pandas dataframe
... without CPU/GPU optimization (sorted from fastest to slowest):
In [107]: %timeit df['Year'].astype(str) + df['quarter']
10 loops, best of 3: 131 ms per loop
In [106]: %timeit df['Year'].map(str) + df['quarter']
10 loops, best of 3: 161 ms per loop
In [108]: %timeit df.Year.str.cat(df.quarter)
10 ...
Find intersection of two nested lists?
... The average case of "val in s2" is O(1) according to wiki.python.org/moin/TimeComplexity#set - thus over n operations the expected time is O(n) (whether the worst-case time is O(n) or O(n^2) depends on whether this average case represents an amortized time or not, but this isn't very important in p...