大约有 43,000 项符合查询结果（耗时：0.0605秒） [XML]
What is the difference between native code, machine code and assembly code?
...f it into the machine code version of the program. The point being C/C++, etc often does not compile straight to machine code it invisible to the user does a two or three step on the way. TCC for example is an exception to this it does go directly to machine code.
– old_timer
...
var functionName = function() {} vs function functionName() {}
...nction declaration inside a control structure like try, if, switch, while, etc., like this:
if (someCondition) {
function foo() { // <===== HERE THERE
} // <===== BE DRAGONS
}
And since they're processed before step-by-step code is run, it's tricky to know what ...
O(nlogn) Algorithm - Find three evenly spaced ones within binary string
...idea of thinking of 11011 as the polynomial with coefficients [1,1,0,1,1], etc. This is a clever and often useful idea, which goes all the way back to Euler. [See Wilf's awesome book "generatingfunctionology" for a modern exposition: math.upenn.edu/~wilf/DownldGF.html ] So it depends on whether the ...
I need to securely store a username and password in Python, what are my options?
...B_FILE, 'w') as f:
pickle.dump(db, f)
def retrieve(key):
''' Fetch key-value pair.'''
return decrypt(db[key], getSaltForKey(key))
def require(key):
''' Test if key is stored, if not, prompt the user for it while hiding their input from shoulder-surfers.'''
if not key in db:...
Big-O for Eight Year Olds? [duplicate]
...lgorithms fall into. Then, you can look at each of those to come up with sketches of what typical algorithms of that time complexity do.
For practical purposes, the only O()'s that ever seem to matter are:
O(1) "constant time" - the time required is independent of the size of the input. As a roug...
Android Camera Preview Stretched
...e screen. I have noticed, several popular apps such as Snapchat, WhatsApp, etc works the same way.
All you have to do is add this to the onMeasure method:
float camHeight = (int) (width * ratio);
float newCamHeight;
float newHeightRatio;
if (camHeight < height) {
newHeightR...
MySQL order by before group by
...by clause, or that are not used in an aggregate function (MIN, MAX, COUNT, etc.).
Correct use of extension to GROUP BY clause
This is useful when all values of non-aggregated columns are equal for every row.
For example, suppose you have a table GardensFlowers (name of the garden, flower that gro...
When do we have to use copy constructors?
...creating a separate worker thread
allocating a separate OpenGL framebuffer
etc
Self-registering objects
Consider a class where all objects - no matter how they have been constructed - MUST be somehow registered. Some examples:
The simplest example: maintaining the total count of currently exi...
Do sealed classes really offer performance Benefits?
...can use call instead of callvirt as it doesn't have to check for virtuals, etc. As proven above, this is not true.
My next thought was that even though the MSIL is identical, perhaps the JIT compiler treats sealed classes differently?
I ran a release build under the visual studio debugger and view...
What's the difference between deadlock and livelock?
...eadlock: situation where nobody progress, doing nothing (sleeping, waiting etc..). CPU usage will be low;
Livelock: situation where nobody progress, but CPU is spent on the lock mechanism and not on your calculation;
Starvation: situation where one procress never gets the chance to run; by pure ba...