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Should I return EXIT_SUCCESS or 0 from main()?
...eing conflicting answers: should the main routine of a C++ program return 0 or EXIT_SUCCESS ?
8 Answers
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How do I check to see if a value is an integer in MySQL?
...lar expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
share
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improve...
Why `null >= 0 && null
...ncrements the value of a variable by 1 if its type is number and assigns 0 to the variable if not, where the variable is initially null or undefined .
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What does {0} mean when initializing an object?
When {0} is used to initialize an object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
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Vagrant reverse port forwarding?
...ROR -o IdentitiesOnly=yes -i ~/.vagrant.d/insecure_private_key vagrant@127.0.0.1
SSH supports forwarding ports in the direction you want with the -R guestport:host:hostport option. So, if you wanted to connect to port 12345 on the guest and have it forwarded to localhost:80, you would use this comm...
How do SO_REUSEADDR and SO_REUSEPORT differ?
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+100
Welcome ...
CSS3 Transparency + Gradient
...round-image: -webkit-gradient(
linear, left top, left bottom, from(rgba(50,50,50,0.8)),
to(rgba(80,80,80,0.2)), color-stop(.5,#333333)
);
(src)
/* mozilla example - FF3.6+ */
background-image: -moz-linear-gradient(
rgba(255, 255, 255, 0.7) 0%, rgba(255, 255, 255, 0) 95%
);
(src)
Apparent...
Delete rows from a pandas DataFrame based on a conditional expression involving len(string) giving K
...ions have worked for me, except the one posted by @4lberto . I'm on pandas 0.23.4 and python 3.6
– goelakash
Aug 25 '18 at 13:22
1
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Double vs. BigDecimal?
...s a certain precision. Working with doubles of various magnitudes (say d1=1000.0 and d2=0.001) could result in the 0.001 being dropped alltogether when summing as the difference in magnitude is so large. With BigDecimal this would not happen.
The disadvantage of BigDecimal is that it's slower, and ...
How do multiple clients connect simultaneously to one port, say 80, on a server? [duplicate]
... don't get is how multiple clients can simultaneously connect to say port 80. I know each client has a unique (for their machine) port. Does the server reply back from an available port to the client, and simply state the reply came from 80? How does this work?
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