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Why is processing a sorted array slower than an unsorted array?
...rted behaving the way I predicted: the sorted version was a little faster. Moreover, the unsorted version became twice as fast! So the numbers with struct are 2s unsorted vs. 1.9s sorted.
– dasblinkenlight
Dec 24 '12 at 21:31
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What's a concise way to check that environment variables are set in a Unix shell script?
...he Bourne Shell (1978 or thereabouts). The ${var:?} construct is slightly more recent: I think it was in System III UNIX circa 1981, but it may have been in PWB UNIX before that. It is therefore in the Korn Shell, and in the POSIX shells, including specifically Bash.
It is usually documented in th...
How can I add new keys to a dictionary?
...nt to create a dictionary just to update one key. Do this only if you have more than 1 key (there may be a threshold above which it's better to create a dict)
– Jean-François Fabre♦
Aug 1 '18 at 21:42
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What is the difference between and ?
...sing elements (see 7.3)), of which span is one of them, among many others. Moreover, this is not an answer to the OP's question: it doesn't tell anything about the difference between p and div. And please read How do comment replies work?
– Marcel Korpel
Aug 1 ...
Multiple Updates in MySQL
... answer assumes the ID is a unique key (can be primary as others said) but more importantly it assumes there are no other unique keys. If there are any, it can throw a spanner in the works.
– Steve Horvath
Dec 3 '14 at 5:43
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iOS 7 status bar back to iOS 6 default style in iPhone app?
...1) UINavigationController altering the height part.Please explain it a bit more. thanks
– user1010819
Oct 31 '13 at 16:12
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How to check if AlarmManager already has an alarm set?
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Show dialog from fragment?
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Unfortunately this approach is a bit more verbose than the classic managed dialogs approach of previous Android revisions, but it is now the preferred method. You can avoid referencing the Activity entirely by using the putFragment and getFragment methods of Fra...
Why is Java's SimpleDateFormat not thread-safe? [duplicate]
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How safe is it to store sessions with Redis?
... hard-disk. You can go through http://redis.io/topics/persistence to learn more, but at a high level, here are your options -
If you cannot afford losing any sessions, set appendfsync always in your configuration file. With this, Redis guarantees that any write operations are saved to the disk. T...