Tutorial by Examples: n

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...

About Akavache Akavache is an incredibly useful library providing reach functionality of caching your data. Akavache provides a key-value storage interface and works on the top of SQLite3. You do not need to keep your schema synced as it's actually No-SQL solution which makes it perfect for most of...

CAShapeLayer *mask = [[CAShapeLayer alloc] init]; mask.frame = CGRectMake(50, 50, 100, 100); CGFloat width = 100; CGFloat height = 100; CGMutablePathRef path = CGPathCreateMutable(); CGPathMoveToPoint(path, nil, 30, 30); CGPathAddLineToPoint(path, nil, width, 30); CGPathAddLine...

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...

Channel uses a Buffer to read/write data. A buffer is a fixed sized container where we can write a block of data at once. Channel is a quite faster than stream-based I/O. To read data from a file using Channel we need to have the following steps- We need an instance of FileInputStream. FileInput...

Swift: if let url = URL(string: "mailto://[email protected]") { 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, ...

This variable is used to set input record separator, by default a newline. awk 'BEGIN{RS=","} {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 turn on the vim spell checker run :set spell. To turn it off run :set nospell. If you always want the spell checker to be on, add set spell to your vimrc. You can turn spelling on only for certain filetypes using an auto command. Once the spell checker is on, misspelled words will be highligh...

#!/bin/bash # Script name : pingnmap # Scenario : The systems admin in company X is tired of the monotonous job # of pinging and nmapping, so he decided to simplify the job using a script. # The tasks he wish to achieve is # 1. Ping - with a max count of 5 -the given IP address/domain. AND/OR ...

Use "-x" to enable debug output of executed lines. It can be run on an entire session or script, or enabled programmatically within a script. Run a script with debug output enabled: $ bash -x myscript.sh Or $ bash --debug myscript.sh Turn on debugging within a bash script. It may ...