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How to get object length [duplicate]
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This is actually worse than using a simple loop and counter because of the added overhead of the callback function.
– nullability
Feb 19 '13 at 17:35
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What does |= (ior) do in Python?
...s1 |= s2 # 2
>>> s1.__ior__(s2) # 3
where the final value of s1 is equivalent either by:
an assigned OR operation
an in-place OR operation
an in-place OR operation via special method++
Example
Here we a...
What is the most accurate way to retrieve a user's correct IP address in PHP?
.... In a few minutes I will update the code.
– Corey Ballou
Jan 9 '10 at 13:37
35
-1 this is vulne...
Are duplicate keys allowed in the definition of binary search trees?
...cluded. For example, the example algorithms in the MIT Algorithms book usually present examples without duplicates. It is fairly trivial to implement duplicates (either as a list at the node, or in one particular direction.)
Most (that I've seen) specify left children as <= and right children ...
Python: using a recursive algorithm as a generator
...h a natural recursive solution. Now it happens that, even for relatively small input, the sequences are several thousands, thus I would prefer to use my algorithm as a generator instead of using it to fill a list with all the sequences.
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If threads share the same PID, how can they be identified?
... +---------+
| process |
_| pid=42 |_
_/ | tgid=42 | \_ (new thread) _
_ (fork) _/ +---------+ \
/ +---------+
+---------+ | ...
When should I use C++14 automatic return type deduction?
...tatement boundaries we make types explicit, within expressions they are usually implicit but we can make them explicit with casts". C++11 and C++1y introduce type deduction tools so that you can leave out the type in new places.
Sorry, but you're not going to solve this up front by making general r...
How to make an app's background image repeat
I have set a background image in my app, but the background image is small and I want it to be repeated and fill in the whole screen. What should I do?
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How efficient is locking an unlocked mutex? What is the cost of a mutex?
... access to the object happens often, then multiple locks would increase parallelism. At the cost of maintainability, since more locking means more debugging of the locking.
How efficient is it to lock a mutex? I.e. how much assembler instructions are there likely and how much time do they take (...
static const vs #define
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Personally, I loathe the preprocessor, so I'd always go with const.
The main advantage to a #define is that it requires no memory to store in your program, as it is really just replacing some text with a literal value. It also has...