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Why would I ever use push_back instead of emplace_back?
... constructors are supposed to be safe. If you can implicitly construct a U from a T, you are saying that U can hold all of the information in T with no loss. It is safe in pretty much any situation to pass a T and no one will mind if you make it a U instead. A good example of an implicit constructor...
What is the C runtime library?
..., on UNIX the floating point functions are traditionally stored separately from the rest). That big file is typically something on the same general order as a zip file, but without any compression, so it's basically just some little files collected together and stored together into one bigger file. ...
Sorting 1 million 8-decimal-digit numbers with 1 MB of RAM
... Once VALUE reaches zero you should have transmitted all integers in order from largest to smallest to the destination, and have only used about 47 bits of RAM for the two persistent variables (and whatever small amount you need for the temporary values).
I know this is horrible, and I know there c...
How do you convert a time.struct_time object into a datetime object?
... time tuple (in localtime) into seconds since the Epoch, then use datetime.fromtimestamp() to get the datetime object.
from datetime import datetime
from time import mktime
dt = datetime.fromtimestamp(mktime(struct))
shar...
Iterating C++ vector from the end to the beginning
Is it possible to iterate a vector from the end to the begin?
12 Answers
12
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Are HTTPS URLs encrypted?
... are 3 of them - not versions, fields that each contain a version number!)
From https://www.ietf.org/rfc/rfc3546.txt:
3.1. Server Name Indication
[TLS] does not provide a mechanism for a client to tell a server
the name of the server it is contacting. It may be desirable for
clients to provi...
Get person's age in Ruby
I'd like to get a person's age from its birthday. now - birthday / 365 doesn't work, because some years have 366 days. I came up with the following code:
...
Is short-circuiting logical operators mandated? And evaluation order?
... @Joe: but return value and arguments of the operator may change from boolean to something else. I used to implement "special" logic with THREE values ("true", "false" and "unknown"). Return value is deterministic, but short-circuiting behaviour is not appropriate.
– ...
getSupportActionBar from inside of Fragment ActionBarCompat
...ort library. I'm trying to figure out how to use the getSupportActionBar from within a fragment. My activity that hosts the fragment extends ActionBarActivity , but I don't see a similar support class for Fragments.
...
combinations between two lists?
...ote: This answer is for the specific question asked above. If you are here from Google and just looking for a way to get a Cartesian product in Python, itertools.product or a simple list comprehension may be what you are looking for - see the other answers.
Suppose len(list1) >= len(list2). Th...