Inconsistent argv declarations in main()
What should main() return in C and C++?
The preimage of a subset If $A\subseteq B$ under what conditions is $f^{-1}(A) \subseteq f^{-1}(B)$, where $f^{-1}$ is the preimage, not  the inverse. Inertial forces and centre of mass Is inertial force always attached to the centre of mass of the object? Why? What rules cause this to happen?  See the  below of the leaned bike in a corner.    The force $m\frac{v^2}{r}$ pointing to the right is the centrifugal force (inertial force - because it's a rotating reference frame, therefore a non-inertial reference frame). It is attached to the centre of gravity of the bike.  I'm thinking that inertial force is attached to the centre of mass because of the fact that it should simply avoid creating a torque on the object. That's intuitive, but there must be a general rule that allows us to conclude that. Post to facebook fan page as a user Redundant prepositions? This is a tooltip in an application:     Identifies the site name to which the GL code belongs to.   Can I say that it is incorrect to use "to" twice here and we should remove 1 of them?  Other examples:       Identifies the vendor to which the port speed is associated with.   Provides the vendor to which the milestone is associated with.   (They are both tooltips, too)  The repetitions here are incorrect, aren't they? Please confirm. I think it would be a very useful and quality-improving feature.  As for me, when I speak on something, I often have a visual representation of how it works, or something. It's obvious there are many things (in algorithms, or, say, UI) which are much easier understood with pictures and diagrams, than from scarce text.  So I'd really like here to be a special answer form, where you can attach some visual things to better explain your ideas.  I imagine this form as just a canvas with few painting tools and some basic blocks and patterns. Alternating binomial sum with intervals of two Fix integer $n\geq 1$. Consider the number $$1-\binom{n}{2}+\binom{n}{4}-\binom{n}{6}+\cdots$$where the sum continues as long as the lower number in the binomial is $\leq n$. Is there a way to simplify this sum?   The first few values are $1, 0, -2, -4, -4$. Most people say I wish I could, I wish you would.    Can we use I wish I can, I wish you will?    I'd like to know what the main differences between the usage of can/will and could/would are when wishing.  Is it related to the subjunctive? Because one says “I wish I were”, not “I wish I am”, so are would and could the subjunctive forms of can and will?  Or is it something else entirely? Difference between "I have got" and "I have gotten" UnboundLocalError: local variable 'url_request' referenced before assignment For any symbol, how can I get the full context-qualified name of the symbol as a string? Plotting solutions to NDSolve Is there any shortcut/easy way to switch this system proxy settings? Why are there no line numbers in the code listings? Would it make discussing code easier if you could simply refer to a particular line or range, or am I wrong? What is the easiest way to export just the selected objects in Illustrator? The title says it all, I want to know what the simplest way to export the selected objects.  In Inkscape, there is a menu option called export selected which does just this.    The aforementioned option lets you export the selection as a composite image or as a batch of individual images.  Both would be nice, but in this scenario I want to export the selected objects as a single image.  I can already create a new document, and paste in the selected items.  I am looking for a way that is easier than this.  How can I save / output / export only the objects I currently have selected, to an image file, in Adobe Illustrator CS5? Finding a replacement for the scoreboard player test In this sentence:  "We would also accept an international transfer, but in that case we would ask you to pay your bank's charges at the time of the instruction to ensure that we received the full amount"  is it correct to use "received" or should it be in present tense? What is the significance of momentum? I just want to get an idea what  is. I know the mathematical meaning that momentum is $mv$ where $v$ is velocity. But I don't know its significance. Like I know that Acceleration is how velocity is changing with respect to time, I wanted to get feel of what momentum really is? Fixing geometry validity errors in QGIS 2? Not getting Rep Notification for new up votes So just a little while ago i was flipping out because i was 2 rep away from my 10k rep goal    but then all of a sudden it was then 10,008 rep because someone upvoted me. however i didn't get any notification about this +10  [    now as you can see in the screenshots above, over the past 2 days i got 2 upvotes to a question i posted, however the notifications only shows 1 +10 notification. and they system knows i got the upvote because i knew that i now have access to mod tools.  I am on a Windows 10 Laptop using Chrome 78.0.3904.97 (Official Build) (64-bit) Merge array items into string