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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
...s no such thing as "unsigned integer overflow") means undefined behaviour. And this means anything can happen, and discussing why does it happen under the rules of C++ doesn't make sense.
C++11 draft N3337: §5.4:1
If during the evaluation of an expression, the result is not mathematically de...
How can I grep hidden files?
I am searching through a Git repository and would like to include the .git folder.
10 Answers
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Stripping everything but alphanumeric chars from a string in Python
...intable (part of the built-in string module). The use of compiled '[\W_]+' and pattern.sub('', str) was found to be fastest.
$ python -m timeit -s \
"import string" \
"''.join(ch for ch in string.printable if ch.isalnum())"
10000 loops, best of 3: 57.6 usec per loop
$ python -m timeit -...
Java Class that implements Map and keeps insertion order?
...or most cases; TreeMap has O(log n) performance for containsKey, get, put, and remove, according to the Javadocs, while LinkedHashMap is O(1) for each.
If your API that only expects a predictable sort order, as opposed to a specific sort order, consider using the interfaces these two classes implem...
Why does HTML think “chucknorris” is a color?
How come certain random strings produce colors when entered as background colors in HTML? For example:
9 Answers
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How to respond with HTTP 400 error in a Spring MVC @ResponseBody method returning String?
...elow for 400
return new ResponseEntity<>(HttpStatus.BAD_REQUEST);
and for correct request
return new ResponseEntity<>(json,HttpStatus.OK);
UPDATE 1
after spring 4.1 there are helper methods in ResponseEntity could be used as
return ResponseEntity.status(HttpStatus.BAD_REQUEST).bo...
How to know if an object has an attribute in Python
...at, if the property is likely to be there most of the time, simply call it and either let the exception propagate, or trap it with a try/except block. This will likely be faster than hasattr. If the property is likely to not be there most of the time, or you're not sure, using hasattr will probably ...
What's the best way to determine the location of the current PowerShell script?
...erShell 3, there was not a better way than querying the
MyInvocation.MyCommand.Definition property for general scripts. I had the following line at the top of essentially every PowerShell script I had:
$scriptPath = split-path -parent $MyInvocation.MyCommand.Definition
...
How do I format date and time on ssrs report?
on SSRS report I need to show todays date and current time
12 Answers
12
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Regex lookahead, lookbehind and atomic groups
...hat I can use them for.
Does somebody have examples so I can try to understand how they work?
3 Answers
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