Tutorial by Examples: o

Consider the Node class having 3 members data, left child pointer and right child pointer like below. public class Node { public int data; public Node left; public Node right; public Node(int data){ this.data = data; } } We can traverse the tree construct...

In order to use icon fonts, just follow the steps below: Add the font file to your project You may create your font icon file from online websites such as icomoon, where you can upload SVG files of the required icons and then download the created icon font. Then, place the .ttf font file into ...

You will need to set your base URL in application/config/config.php If it is not set, then CodeIgniter will try to guess the protocol and path to your installation, but due to the security concerns the hostname will be set to $_SERVER['SERVER_ADDR'] if available, or localhost otherwise. The auto...

First you have to set up a new Scrapy project. Enter a directory where you’d like to store your code and run: scrapy startproject projectName To scrape we need a spider. Spiders define how a certain site will be scraped. Here’s the code for a spider that follows the links to the top voted questi...

CAShapeLayer *circle = [CAShapeLayer layer]; [circle setPath:[[UIBezierPath bezierPathWithOvalInRect:CGRectMake(100, 100, 150, 150)] CGPath]]; [circle setStrokeColor:[[UIColor blueColor] CGColor]]; [circle setFillColor:[[UIColor clearColor] CGColor]]; [[self.view layer] addSublayer:circl...

Imagine you are on the master branch and something is not working as expected (a regression was introduced), but you don't know where. All you know is, that is was working in the last release (which was e.g., tagged or you know the commit hash, lets take old-rel here). Git has help for you, finding...

In your Storyboard, add a UITableView object on your UIViewController and let it cover the entire view. Setup the UITableviewDataSource and UITableviewDelegate connections. Objective-C In your .h file NSMutableArray *arrayForBool; NSMutableArray *sectionTitleArray; In your .m file - (void)vi...

We can directly copy data from a source to a data sink using a loop. In this example, we are reading data from an InputStream and at the same time, writing to an OutputStream. Once we are done reading and writing, we have to close the resource. public void copy(InputStream source, OutputStream dest...

Swift: if let url = URL(string: "mailto://azimov@demo.com") { if UIApplication.shared.canOpenURL(url) { UIApplication.shared.openURL(url) } else { print("Cannot open URL") } } Objective-C: NSURL *url = [NSURL URLWithString:@"mailto://az...

While implementing one of the standard hashing algorithm in awk is probably a tedious task, defining a hash function that can be used as a handle to text documents is much more tractable. A practical situation where such a function is useful is to assign short ids to items given their description, ...

The variable FS is used to set the input field separator. In awk, space and tab act as default field separators. The corresponding field value can be accessed through $1, $2, $3... and so on. awk -F'=' '{print $1}' file -F - command-line option for setting input field separator. awk 'BEGIN ...

This variable is used to set the output field separator which is a space by default. awk -F'=' 'BEGIN { OFS=":" } { print $1 }' file Example: $ cat file.csv col1,col2,col3,col4 col1,col2,col3 col1,col2 col1 col1,col2,col3,col4,col5 $ awk -F',' 'BEGIN { OFS="|" } { $...

This variable is used to set input record separator, by default a newline. awk 'BEGIN{RS=","} {print $0}' file

This variable is used to set output record separator, by default a newline. awk 'BEGIN{ORS=","} {print $0}' file

This variable will give you a total number of fields in the current input record. awk -F',' '{print NF}' file.csv Example: $ cat file.csv col1,col2,col3,col4 col1,col2,col3 col1,col2 col1 col1,col2,col3,col4,col5 $ awk -F',' '{print NF}' file.csv 4 3 2 1 5

let let num=1+2 let num="1+2" let 'num= 1 + 2' let num=1 num+=2 You need quotes if there are spaces or globbing characters. So those will get error: let num = 1 + 2 #wrong let 'num = 1 + 2' #right let a[1] = 1 + 1 #wrong let 'a[1] = 1 + 1' ...

Setup your test environment Download Espresso Set the instrumentation runner Example build.gradle file Analytics Add the first test Running tests This guide covers installing Espresso using the SDK Manager and building it using Gradle. Android Studio is recommended. Setup your test envir...

To set the word list that vim will use for spell checking set the spelllang option. For example :set spelllang=en # set to English, usually this is the default :set spelllang=en_us # set to U.S. English :set spelllang=en_uk # set to U.K. English spellings :set spelllang=es ...

Simple steps to use scrollview with autolayout. Create a new project with single view application Select the default viewcontroller and change its screen size to iPhone-4inch from attributes inspector. Add a scrollview to your viewcontroller's view as follows and set background color to blue ...

Every single ViewGroup (e.g. LinearLayout, RelativeLayout, CoordinatorLayout, etc.) needs to store information about its children's properties. About the way its children are being laid out in the ViewGroup. This information is stored in objects of a wrapper class ViewGroup.LayoutParams. To include...