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Is it possible to implement a Python for range loop without an iterator variable?
...ou can just live with the extra i variable.
Here is the option to use the _ variable, which in reality, is just another variable.
for _ in range(n):
do_something()
Note that _ is assigned the last result that returned in an interactive python session:
>>> 1+2
3
>>> _
3
F...
URLWithString: returns nil
...llowing API webStringURL = [stringURL stringByAddingPercentEncodingWithAllowedCharacters:NSCharacterSet.URLQueryAllowedCharacterSet];
– Rushabh
Oct 24 '17 at 0:37
...
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...
Without the update-and-join notation (not all DBMS support that), use:
UPDATE QuestionTrackings
SET QuestionID = (SELECT QuestionID
FROM AnswerTrackings
WHERE AnswerTrackings.AnswerID = QuestionTrackings.AnswerID)
...
Why would iterating over a List be faster than indexing through it?
...nt head -> item1 -> print item1 -> item2 -> print item2 etc.
all in a single traversal, which is O(N).
Now, going to the other implementation of List which is ArrayList, that one is backed by a simple array. In that case both of the above traversals are equivalent, since an array is c...
Storing sex (gender) in database
...
I'd call the column "gender".
Data Type Bytes Taken Number/Range of Values
------------------------------------------------
TinyINT 1 255 (zero to 255)
INT 4 - 2,147,483,...
Python's json module, converts int dictionary keys to strings
...which implement a __hash__ method. (The Lua docs suggest that it automatically uses the object's ID as a hash/key even for mutable objects and relies on string interning to ensure that equivalent strings map to the same objects).
In Perl, Javascript, awk and many other languages the keys for hash...
Parsing Visual Studio Solution files
...gage in the meta discussions if you want to learn more about this. I personally find that it's a bit crazy sometimes. Please note that I had absolutely nothing to do with your edits getting shut down. The proper way though I think to add you edits is actually to repost everything as another answer. ...
在 App Inventor 2 中使用图像 · App Inventor 2 中文网
...crashes[a] when they try to run it, with an error message like:
Failed to allocate a 25165836 byte allocation with 3395432 free bytes and 3MB until OOM
What’s happening here is that the app is is running out of memory (OOM). In the case of the message above, the phone is trying to allocate 25 m...
dismissModalViewControllerAnimated deprecated
...
The word modal has been removed; As it has been for the presenting API call:
[self presentViewController:vc animated:NO completion:nil];
The reasons were discussed in the 2012 WWDC Session 236 - The Evolution of View Controllers on iOS Video. Essentially, view controllers presented by this API...
Calculating how many minutes there are between two times
...s', this will return only the minutes of timespan [0~59], to return sum of all minutes from this interval, just use 'span.TotalMinutes'.
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