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Is multiplication and division using shift operators in C actually faster?
Multiplication and division can be achieved using bit operators, for example
19 Answers
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Meaning of $? (dollar question mark) in shell scripts
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This is the exit status of the last executed command.
For example the command true always returns a status of 0 and false always returns a status of 1:
true
echo $? # echoes 0
false
echo $? # echoes 1
From the manual: (acessible by calling man bash in your shell)
$?...
Are the shift operators () arithmetic or logical in C?
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When shifting left, there is no difference between arithmetic and logical shift. When shifting right, the type of shift depends on the type of the value being shifted.
(As background for those readers unfamiliar with the difference, a "logical" right shift by 1 bit shifts all the bits ...
How to merge dictionaries of dictionaries?
...for key in b:
if key in a:
if isinstance(a[key], dict) and isinstance(b[key], dict):
merge(a[key], b[key], path + [str(key)])
elif a[key] == b[key]:
pass # same leaf value
else:
raise Exception('Conflict at %...
python assert with and without parenthesis
...through a full interpreter, not through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion message is optional, you've essentiall...
What is the difference between concurrency and parallelism?
What is the difference between concurrency and parallelism?
37 Answers
37
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Generate random numbers following a normal distribution in C/C++
How can I easily generate random numbers following a normal distribution in C or C++?
18 Answers
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How to concatenate two MP4 files using FFmpeg?
...ess hence why I chose ffmpeg. I'm converting the two files into .ts files and then concatenating them and then trying to encode that concated .ts file. The files are h264 and aac encoded and I'm hoping to keep the quality the same or as close to original as possible.
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Int division: Why is the result of 1/3 == 0?
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The two operands (1 and 3) are integers, therefore integer arithmetic (division here) is used. Declaring the result variable as double just causes an implicit conversion to occur after division.
Integer division of course returns the tr...
Finding the number of days between two dates
...I think returning a negative number of days provides relevant information. And you should be using $your_date-$now, if you want a future date to return a positive integer.
– Tim
Mar 2 '12 at 18:49
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