Not getting desired output while using the 'equal to' operator I have written a program, part of which checks whether two strings are equal or not. Although, both the strings when printed individually, come out to be same, however, when equated, the result so obtained is not what is desired. The code is as follows ..      import java.util.*;     import java.lang.*;     import java.io.*;      class GFG      {         public static void main (String[] args)              {                    StringBuilder pattern=new StringBuilder("^coal");                 StringBuilder text=new StringBuilder("coaltar");                 System.out.println(pattern.substring(1));                 System.out.println(text.substring(0,pattern.length()-1));                 if(pattern.charAt(0)=='^')                 {                         if(pattern.substring(1)==text.substring(0,pattern.length()-1))                                 System.out.println("1a");                         else                                 System.out.println("0a");                 }             }     }   The output must be 1a. However, it is coming out to be 0a. Please help.Thank You.
How do I compare strings in Java? I've been using the == operator in my program to compare all my strings so far. However, I ran into a bug, changed one of them into .equals() instead, and it fixed the bug.  Is == bad? When should it and should it not be used? What's the difference?
My question is related to my previous asked one:   I have about 300 shapekeys and want to set the random value for all of them . How to do it using scripting? What's the difference between "uname -r" and "uname -v"? Algebraic closure of $\mathbb F_p$ tikz arc with -latex arrow tip Why the arc does not fit over the circle if we use -latex arrow tip? Maybe some bug or some bad math computations?    MWE  \documentclass[11pt,margin=2pt]{standalone} \usepackage{tikz} \usetikzlibrary{arrows.meta}  \begin{document} \begin{tikzpicture} \draw         (0:1cm) arc (0: 180:1cm) arc (180:0:1cm and 2cm); \draw         (0:1cm) arc (0:-180:1cm); \draw[-&gt;]     (0:1cm) arc (0:  80:1cm); \draw[-latex] (0:1cm) arc (0:- 80:1cm); \end{tikzpicture} \end{document} Is it unreasonable to assign a MySQL database to each user on my site? I'm creating a user-based website. 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One table to document ALL ratings that have been made (that is, Three columns: User, Quote, rating).  That seems reasonable. Is there any problem with that? Trying to overwrite ... which is different from other instances of package I tried to upgrade Intel graphics in ubuntu 16.10 using the official installer. The last stage of unpacking libcairo2 produces an error (see figure).  When I do upgrade I get the same error also:   Preparing to unpack .../0-libcairo2_1.15.2-0intel1_amd64.deb ... Unpacking libcairo2:amd64 (1.15.2-0intel1) over (1.15.2-0intel1) ... dpkg: error processing archive /tmp/apt-dpkg-install-aYhdFd/0 libcairo2_1.15.2-0intel1_amd64.deb (--unpack): trying to overwrite shared '/usr/share/doc/libcairo2/changelog.Debian.gz', which is different from other instances of package libcairo2:amd64 Preparing to unpack .../1-libcairo2_1.15.2-0intel1_i386.deb ... Unpacking libcairo2:i386 (1.15.2-0intel1) over (1.15.2-0intel1) ... dpkg: error processing archive /tmp/apt-dpkg-install-aYhdFd/1-libcairo2_1.15.2-0intel1_i386.deb (--unpack): trying to overwrite shared '/usr/share/doc/libcairo2/changelog.Debian.gz', which is different from other instances of package libcairo2:i386 Errors were encountered while processing: /tmp/apt-dpkg-install-aYhdFd/0-libcairo2_1.15.2-0intel1_amd64.deb /tmp/apt-dpkg-install-aYhdFd/1-libcairo2_1.15.2-0intel1_i386.deb E: Sub-process /usr/bin/dpkg returned an error code (1)   It seems that there is a conflict in thelibcairo releases; if yes, how to resolve it ? Can't start ubuntu-desktop after upgrade to 18.04 After the restart step of upgrading Ubuntu to 18.04, tty is opening instead ubuntu-desktop. And when I enter my login name and password, I am still in the tty. This is happening again in every restart. How can I start the graphical desktop as normal? 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