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How to check if std::map contains a key without doing insert?
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Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.
Alternately my_map.find( key ) != my_map.end() works too.
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What is the purpose of the -m switch?
Could you explain to me what the difference is between calling
3 Answers
3
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Is it ever advantageous to use 'goto' in a language that supports loops and functions? If so, why?
...o this already):
Cleanly exiting a function
Often in a function, you may allocate resources and need to exit in multiple places. Programmers can simplify their code by putting the resource cleanup code at the end of the function, and all "exit points" of the function would goto the cleanup label....
POSTing a @OneToMany sub-resource association in Spring Data REST
...ion resource (considered to be $association_uri in the following), it generally takes these steps:
Discover the collection resource managing comments:
curl -X GET http://localhost:8080
200 OK
{ _links : {
comments : { href : "…" },
posts : { href : "…" }
}
}
Follow the comments l...
Convert Django Model object to dict with all of the fields intact
How does one convert a Django Model object to a dict with all of its fields? All ideally includes foreign keys and fields with editable=False .
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Understanding the difference between __getattr__ and __getattribute__
...oesn't explicitly manage and do that via __getattr__ method.
Python will call this method whenever you request an attribute that hasn't already been defined, so you can define what to do with it.
A classic use case:
class A(dict):
def __getattr__(self, name):
return self[name]
a = A()...
Can I mask an input text in a bat file?
...2/22/2013
::https://groups.google.com/forum/#!topic/alt.msdos.batch.nt/f7mb_f99lYI
@Echo Off
:HInput
SetLocal EnableExtensions EnableDelayedExpansion
Set "FILE=%Temp%.\T"
Set "FILE=.\T"
Keys List >"%File%"
Set /P "=Hidden text ending with Ctrl-C?: " <Nul
Echo.
Set "HInput="
:HInput_
For /F "...
Best practice for Django project working directory structure
I know there is actually no single right way. However I've found that it's hard to create a directory structure that works well and remain clean for every developer and administrator. There is some standard structure in most projects on github. But it does not show a way to organize another files an...
Absolute vs relative URLs
...ed Jan 5 '10 at 9:33
Daniel VassalloDaniel Vassallo
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Split list into smaller lists (split in half)
...6]
B = A[:len(A)//2]
C = A[len(A)//2:]
If you want a function:
def split_list(a_list):
half = len(a_list)//2
return a_list[:half], a_list[half:]
A = [1,2,3,4,5,6]
B, C = split_list(A)
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