swap(int &a, int &b) and swap(int *a, int *b). What is difference?
What are the differences between a pointer variable and a reference variable in C++?
Cross-referencing problem if counter of theorem-like environments is shared The problem is when i share numbering the \cref can't show name, even by \crefname and \autoref show all name Equation.  Here is an MWE:  %&amp;latex \documentclass{amsart}  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % If you want to insert other packages. Insert them here \usepackage{amsthm} \usepackage{hyperref} \usepackage[nameinlink]{cleveref} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  \begin{document}  \numberwithin{equation}{section}  \newtheorem{The}[equation]{Theorem} \crefname{The}{Theorem}{Theorems}  \newtheorem{Dfn}[equation]{Definition} \newtheorem{Lem}[equation]{Lemma} \newtheorem{Prs}[equation]{Proposition} \newtheorem{Crl}[equation]{Corollary} \newtheorem{Rmk}[equation]{Remark}  \begin{The}\label{T1}    Assume ... \end{The}  ... \begin{Dfn}\label{D1}    Assume ... \end{Dfn}  ... \begin{Lem}\label{L1}    Assume ... \end{Lem}  ... \begin{Prs}\label{P1}    Assume ... \end{Prs}  ... \begin{Crl}\label{C1}    Assume ... \end{Crl}  ... \begin{Rmk}\label{R1}    Assume ... \end{Rmk}  \begin{equation}\label{E1}    Assume ... \bigskip \end{equation}  \noindent \cref{T1} \\ \cref{D1} \\ \cref{L1} \\ \cref{P1} \\ \cref{C1} \\ \cref{R1} \\ \cref{E1} \\  \noindent \autoref{T1} \\ \autoref{D1} \\ \autoref{L1} \\ \autoref{P1} \\ \autoref{C1} \\ \autoref{R1} \\ \autoref{E1} \\  \end{document}     How can I solve it? How to add indicator on a light switch to indicate the outdoor 3-way light is on? Have some carriage lights outside my garage that can be turned on from inside the house. It's common that the switch will get flipped and the lights will stay on when they're not wanted.  Is there some way I can add an indicator to the light switch so I can know if the light is on?  Note: the carriage lights are on a 3 way switch. How to change/rewrite the lost password url? I used iThemes Security (formerly Better WP Security) hide back-end functionality to change the login url to /signin however clicking the lost password link /wp-login.php?action=lostpassword now generate a 404  Manually going to /signin?action=lostpassword works.  I came across the following code below which is suppose to make the change to however after some testing it doesn't seem to work  //******************************************************* //Function to change to lost password url //******************************************************** add_filter('site_url',  'wplogin_filter', 10, 3); function wplogin_filter( $url, $path, $orig_scheme ){     $old  = array( "/(wp-login\.php)/");     $new  = array( "signin/"); //this can be change to login or whatever or may remain there     return preg_replace( $old, $new, $url, 1); }   add to .htaccess  RewriteRule ^signin$ wp-login.php   How can i modify the above code in order to change the url for the lost password? Importance of normal distribution Why did the normal distribution become such a popular (important) distribution? I know one reason is because of CLT. Can you please give more reasons? If n is such that every element $(\mathbb{Z}/n\mathbb{Z})^{\times}$ is a root of $x^2-1$. Prove that $n$ divides 24. I have a hard time formulating proofs.  For this problem, I  can see that if $n$ is equal to $8,$ this statement is true.  $(\mathbb{Z}/8\mathbb{Z})^{\times}$ includes elements:  $1,3,5,7$, and all of these are roots of $1-x^2 \pmod 8.$  And obviously $8$ divides $24.$  But how do I prove this without depending on number calculations and only using theorems?  Help Please?  I need a step by step walk through of how to do this proof and what theorems would be appropriate to use. Confusion between register size, address size, data size I started learning about pointers in C++ and I figured I should educate myself a bit on how memory works and is accessed. I read that when we say a processor is 64-bit, it has a 64-bit register and can access 2^64 address locations. I also read that it can fetch 64/8, so 8 bytes of data at a time, but the data bus is not the same thing as the register right? Do they need to be the same size or does that just happen to be the case usually? And is it the size of the register or the data bus size that determines what we refer to it as, such as 32/64-bit? Also is there a difference between register size and address size? WPF CommandParameter is NULL first time CanExecute is called Reading InputStream as UTF-8 Limit $\lim_{n\to \infty} \frac{1}{2n} \log{2n\choose n}$ Inclusion of Fields whose order is a prime power Blue was correct, I need to fix my understanding of this:     Finite fields have cardinality of a prime order because they have a prime subfield that has finite characteristic.    I do not completely understand why finite field of each characteristic is unique. Perhaps we look at a polynomial and express the finite field as a splitting field? And we use uniqueness of splitting fields?  Then, why is it that  $\mathbb F_{p^m} \subseteq \mathbb F_{p^n}$ if and only if $m$ divides $n$? I have a stubborn folder that someone must have created accidentally and that has persisted all this time. I can see it with:  # find /var/www/html -maxdepth 1 -type d   which gives me:  /var/www/html /var/www/html/files /var/www/html/.?   unfortunately the question mark there is not the actual character ?, it merely seems to denote that there is no proper glyph and/or translation for that character. So something like rmdir is out of the question. My system has UTF-8 as the default locale as so many modern Ubuntu systems, but admittedly the folder in question may have originated on a RHEL or CentOS box (tared up and unpacked).  # env|grep LANG LANG=en_US.UTF-8   When trying to cd .\? (as mentioned before it is not actually ?) I get auto-corrected to . by bash and actually end up in /var/www/html/. for some reason. Now if I can't "name" this folder usefully, I cannot access it in any way. How can I get rid of it without putting the whole system in jeopardy?  Now I installed detox already but that only seems to act on files, not folders, according to its documentation and besides it still requires that I be able to name the object somehow to do something with it. datatool with longtable Caption above subtables with subcaption package breaks numbering of following table What does $2^x$ really mean when $x$ is not an integer? Show that if $|f(z)| \leq M |z|^n$ then $f$ is a polynomial max degree n I can't prove this statement, can anybody show me how to prove it?    $$f:\mathbb{C}\rightarrow \mathbb{C} \in \mathcal{O}(\mathbb{C}), \exists n\in \mathbb{N}, R &gt;0 , M&gt;0 : |f(z)| \le M|z|^{n} \ \ \forall |z|&gt;R \Rightarrow \deg(f)\le n $$  To show is that if there exists such an $M$, that then $f$ is a polynomial of max degree $n$. I started like this:   $$f(z) = \sum_{n=0}^{\infty} a_n (z-z_0)^n$$ So if I put this into the inequality: $$|f(z)| = \left| \sum_{n=0}^{\infty} a_n (z-z_0)^n \right| \le M |z|^n .$$ Is there a general formula for image size vs. print size? Cleveref with counters with same name I am trying to use the  package.  I have the following counters defined (hopefully this is the right way to do it!)  \newtheorem{thm}{Theorem}[section] \newtheorem{lemma}[thm]{Lemma} \newtheorem{cor}[thm]{Corollary}   This works as I would like (i.e. Theorem 1.1, Corollary 1.2, Lemma 1.3, etc.)  My problem is \cref always returns Theorem 1.2, Theorem 1.3. I   Perhaps this is not right? (In my preamble)  \crefname{thm}{theorem}{theorem's} \crefname{lemma}{lemma}{lemma's} Difference between SQL batch, statement and RPC? What is the difference between SQL batch, T-SQL statement and Remote Procedure Call? How can I tell if part of the T-SQL code is a batch or statement? Intuitive explanation for how could there be "more" irrational numbers than rational? How do I limit the number of rows returned by an Oracle query after ordering?