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Why start an ArrayList with an initial capacity?
...ated as the list grows.
The larger the final list, the more time you save by avoiding the reallocations.
That said, even without pre-allocation, inserting n elements at the back of an ArrayList is guaranteed to take total O(n) time. In other words, appending an element is an amortized constant-tim...
What is the difference between the add and offer methods in a Queue in Java?
... to method
Collection.add(E), which can fail to
insert an element only by throwing an
exception.
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How to Git stash pop specific stash in 1.8.3?
...syntax stash@{x}, use Git 2.11 (Q4 2016)
See commit a56c8f5 (24 Oct 2016) by Aaron M Watson (watsona4).
(Merged by Junio C Hamano -- gitster -- in commit 9fa1f90, 31 Oct 2016)
stash: allow stashes to be referenced by index only
Instead of referencing "stash@{n}" explicitly, make it possi...
How do I use floating-point division in bash?
...IDTH/$IMG2_WIDTH") without $(( )) (double parentheses) ; which is expanded by the bash before executing command
– Nahuel Fouilleul
Oct 4 '12 at 7:32
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Sample random rows in dataframe
...red Nov 25 '11 at 19:15
John ColbyJohn Colby
20.3k33 gold badges5151 silver badges6767 bronze badges
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Can't subtract offset-naive and offset-aware datetimes
...
UTC doesn't need a timezone, by definition. If the other datetime object is timezone aware then surely that provides the offset relative to UTC. UTC times may not have a timezone but they are not 'naive' and Python is handling this wrongly.
...
INSERT … ON DUPLICATE KEY (do nothing)
...:
simple.
cons:
too slow.
auto-increment key will CHANGE(increase by 1) if there is entry matches unique key or primary key, because it deletes the old entry then insert new one.
2. INSERT IGNORE
pros:
simple.
cons:
auto-increment key will not change if there is entry matches uni...
Distinct by property of class with LINQ [duplicate]
... the first car from each group:
List<Car> distinct =
cars
.GroupBy(car => car.CarCode)
.Select(g => g.First())
.ToList();
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C++ inheritance - inaccessible base?
...ass are limited to private. struct inheritance on the other hand is public by default.
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Qt: *.pro vs *.pri
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A .pro file is what you would run QMake on. A .pri file is included by a .pro file. Other than that there is not much of a difference between the two.
Example usage could be if you have different builds which need different options. You could put shared information in the .pro, while deferr...