I am getting the following error:     error: non-static method binarySearch(int[],int,int,int) cannot be   referenced from a static context                  System.out.println(binarySearch(arr,0,n-1,val));   class BinarySearch {      int binarySearch(int arr[], int i, int len, int val) {         if (len &gt;= 1) {             int mid = i + (len - 1) / 2;             if (arr[mid] == val)                 return mid;             if (arr[mid] &gt; val)                 return binarySearch(arr, i, mid - 1, val);              return binarySearch(arr, mid + 1, len, val);         }         return -1;     }      public static void main(String args[]) {          int arr[] = {1, 5, 7, 9, 55, 67};         int val = 7;         int n = arr.length;         System.out.println(binarySearch(arr, 0, n - 1, val));     } }
The very common beginner mistake is when you try to use a class property "statically" without making an instance of that class. It leaves you with the mentioned error message:     You can either make the non static method static or make an instance of that class to use its properties.   Why? I am not asking for solutions. I would be grateful to know what is the reason behind it. The very core reason!  private java.util.List&lt;String&gt; someMethod(){     /* Some Code */     return someList;             }  public static void main(String[] strArgs){                // The following statement causes the error. You know why..     java.util.List&lt;String&gt; someList = someMethod();          }
I have knowledge about 'Kile' more or less. Now  I am using 'Texmaker'. But  there is a problem in it. In Kile when we write \begin{env} it automatically write \end{env} from the following :  Settings => Configure Kile => LaTeX => Environments => making tick mark on "Automatically complete \begin{env} with \end{env}" we can set it. But in 'Texmaker' automatic environment is not working. How can I do so. Windows Phone ReverseGeocoding to get Address from Lat and Long Is the set of real matrices diagonalizable in $\mathcal M_n(C)$ dense in the set of all companion matrices? Let $\mathcal E=\{A \in \mathcal M_n(\mathbb R): A \text{ is of companion form} \}$. That is, $A$ has the following form \begin{align*} A=\begin{pmatrix}  0 &amp; \cdots &amp; 0&amp; -a_{0} \\  1 &amp; \cdots &amp; 0 &amp; -a_{1}\\ \vdots &amp;\ddots &amp; \vdots &amp;\vdots \\ 0 &amp;\cdots &amp; 1 &amp; -a_{n-1} \end{pmatrix}. \end{align*} Let $\mathcal D = \{A \in \mathcal M_n(\mathbb R): A \text{ is diagonalizable in $\mathcal M_n(\mathbb C)$}\}$. We know $\mathcal D$ is dense in $\mathcal M_n(\mathbb R)$. I am wondering whether $\mathcal E \cap \mathcal D$ is dense in $\mathcal E$. The set $\mathcal E$ is closed. It is not clear to me whether this statement is true. Ought we only form beliefs based on sufficient empirical evidence? What happens with lethargy when Haste is cast again on a creature before first cast runs out? Value passed with request.setAttribute() is not available by request.getParameter() RC4 , Is it possible to find the key if we know the plaintext and ciphertext? Is it possible to find the key if we know the plaintext and ciphertext with RC4. How should I write the algorithm? Pointer to class data member "::*" Date(time) ranges using `datetime2` My players have been scheming with rapid entry tactics for the megadungeon I've recently started running. Unfortunately, the monsters are aware of the adventurers, and this has lead to a weird question of priority. Given the following situation (which I'm pretty sure is going to happen next session in some form or another) what happens?     Alice the adventurer readies an action; if her teammate Carlos opens   the door, she's going to throw the alchemists fire through the door,   which should do enough damage to kill any goblins hiding there.      Meanwhile, on the other side of the door, Bob the goblin is lying in   wait. He readies an action; if the door opens, he's going to hit the   switch to open the trapdoor in the next room, which should drop any    pesky adventurers into a pit with spikes at the bottom.      Carlos opens the door.   I know what happens when , but what happens when multiple readied actions get triggered at the same time? My guess would be an opposed reflex save or initiative check of some kind to see who goes first, but that's entirely just intuition speaking. The rulebook doesn't seem to speak to the issue. Optimize table layout ls -la symbolics... what does that last symbol mean? Why is using a wild card with a Java import statement bad? Statistical inference when the sample "is" the population Finding the fallacy in this broken proof Proof of a formula for the power set of a union of two sets I need to prove that:  $2^{A\cup B} =\left \{ X\cup Y \mid X\in 2^{A}, Y\in2^{B} \right \}$  Note that $2^{A} = P(A)$ (The power set of A).  While I can prove the Right - Left direction fairly easily, It seems very hard for me to prove the Left - Right direction. Can I get some help with that?  How do I prove that $t\in2^{A\cup B}$ makes $t\in \left \{ X\cup Y \mid X\in 2^{A}, Y\in2^{B} \right \}$? What spell targets count for the Graviturgy Magic wizard's Gravity Well feature? The  feature from the  (EGtW, p. 185) triggers &quot;whenever you cast a spell on a creature&quot;, and has an effect &quot;if the target is willing to move, the spell hits it with an attack, or it fails a saving throw against the spell.&quot; It's not clear to me what kinds of spells can actually trigger this feature. Based on the singular phrasing of &quot;on a creature&quot; and the later use of the word &quot;target&quot;, I would normally read this as only applying to spells that explicitly target creatures (and perhaps only those with a single target, in contrast to the phrasing of the  feature of the  wizard, for example). However, spells that target a location can use the word target in a different sense (see ). What's actually going on here? Does this feature only work on targeted spells? Or does it function for area of effect spells as well? Or is this just an ambiguous phrasing that will rely on the DM's ruling? How to properly restart unity? I am looking for a transparent screensaver. Or a way for there to be no screen saver, but instead of locking, it disables the mouse and most of the keyboard, until I hit an unlock key. The following example works as expected:  \documentclass{article} \usepackage[table]{xcolor} \usepackage{makecell, multirow}     \renewcommand\theadfont{\normalsize\bfseries\color{white}}     \renewcommand{\theadgape}{} \usepackage{hhline}  \begin{document} \centering     \setlength\arrayrulewidth{2pt}     \arrayrulecolor{yellow}     \def\clinecolor{\hhline{&gt;{\arrayrulecolor{yellow}}--%                             &gt;{\arrayrulecolor{gray}}-}}     \setlength\extrarowheight{2pt} \begin{tabular}{ c | c | c }%     \rowcolor{gray} \multicolumn{2}{c|}{\thead{AAA -- BBBB}}    &amp;                                   \\     \clinecolor     \rowcolor{gray} \color{white} AAA   &amp;   \color{white} BBB   &amp;   \multirow{-2}{*}{\thead{CCC}}   \\     \hhline{&gt;{\arrayrulecolor{yellow}}-|-|-}     \rowcolor{gray!25} aaa                 &amp;   bbb                 &amp;   ccc                             \\     \hline     \rowcolor{gray!25} ddd             &amp;   eee                 &amp;   fff     \end{tabular} \end{document}     But the following not:  \documentclass[xcolor=table]{beamer} \usepackage{makecell, multirow}     \renewcommand\theadfont{\normalsize\bfseries\color{white}}     \renewcommand{\theadgape}{} \usepackage{hhline}  \begin{document} \begin{frame} \frametitle{test} \centering     \setlength\arrayrulewidth{2pt}     \arrayrulecolor{yellow}     \def\clinecolor{\hhline{&gt;{\arrayrulecolor{yellow}}--%                             &gt;{\arrayrulecolor{gray}}-}}     \setlength\extrarowheight{2pt} \begin{tabular}{ c | c | c }%     \rowcolor{gray} \multicolumn{2}{c|}{\thead{AAA -- BBBB}}    &amp;                                   \\     \clinecolor     \rowcolor{gray} \color{white} AAA   &amp;   \color{white} BBB   &amp;   \multirow{-2}{*}{\thead{CCC}}   \\     \hhline{&gt;{\arrayrulecolor{yellow}}-|-|-}     \rowcolor{gray!25} aaa                 &amp;   bbb                 &amp;   ccc                             \\     \hline     \rowcolor{gray!25} ddd             &amp;   eee                 &amp;   fff                             \\     \hhline{|-|-|-|}     \end{tabular} \end{frame} \end{document}     Why are the in beamer rules so strangely misplaced? Is there some workaround?