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Jsoup can be used to extract links and email address from a webpage, thus "Web email address collector bot" First, this code uses a Regular expression to extract the email addresses, and then uses methods provided by Jsoup to extract the URLs of links on the page. public class JSoupTest {...

After starting a merge, you might want to stop the merge and return everything to its pre-merge state. Use --abort: git merge --abort

This example uses the Cars Table from the Example Databases. UPDATE Cars SET Status = 'READY' This statement will set the 'status' column of all rows of the 'Cars' table to "READY" because it does not have a WHERE clause to filter the set of rows.

This example uses the Cars Table from the Example Databases. UPDATE Cars SET Status = 'READY' WHERE Id = 4 This statement will set the status of the row of 'Cars' with id 4 to "READY". WHERE clause contains a logical expression which is evaluated for each row. If a...

This example uses the Cars Table from the Example Databases. UPDATE Cars SET TotalCost = TotalCost + 100 WHERE Id = 3 or Id = 4 Update operations can include current values in the updated row. In this simple example the TotalCost is incremented by 100 for two rows: The TotalCost of Car #3 i...

The general syntax for declaring a one-dimensional array is type arrName[size]; where type could be any built-in type or user-defined types such as structures, arrName is a user-defined identifier, and size is an integer constant. Declaring an array (an array of 10 int variables in this case) i...

Sometimes it's necessary to set an array to zero, after the initialization has been done. #include <stdlib.h> /* for EXIT_SUCCESS */ #define ARRLEN (10) int main(void) { int array[ARRLEN]; /* Allocated but not initialised, as not defined static or global. */ size_t i; for(i ...

Arrays have fixed lengths that are known within the scope of their declarations. Nevertheless, it is possible and sometimes convenient to calculate array lengths. In particular, this can make code more flexible when the array length is determined automatically from an initializer: int array[] = {...

Accessing array values is generally done through square brackets: int val; int array[10]; /* Setting the value of the fifth element to 5: */ array[4] = 5; /* The above is equal to: */ *(array + 4) = 5; /* Reading the value of the fifth element: */ val = array[4]; As a side effect of...

You can filter what routes are available using constraints. There are several ways to use constraints including: segment constraints, request based constraints advanced constraints For example, a requested based constraint to only allow a specific IP address to access a route: constraints(...

The <nav> element is primarily intended to be used for sections that contain main navigation blocks for the website, this can include links to other parts of the web page (e.g. anchors for a table of contents) or other pages entirely. Inline items The following will display an inline set of ...

String literals in Swift are delimited with double quotes ("): let greeting = "Hello!" // greeting's type is String Characters can be initialized from string literals, as long as the literal contains only one grapheme cluster: let chr: Character = "H" // valid let chr...

Git will usually open an editor (like vim or emacs) when you run git commit. Pass the -m option to specify a message from the command line: git commit -m "Commit message here" Your commit message can go over multiple lines: git commit -m "Commit 'subject line' message here Mor...

var a = Math.random(); Sample value of a: 0.21322848065742162 Math.random() returns a random number between 0 (inclusive) and 1 (exclusive) function getRandom() { return Math.random(); } To use Math.random() to get a number from an arbitrary range (not [0,1)) use this function to get a...

git rm filename To delete the file from git without removing it from disk, use the --cached flag git rm --cached filename

Extensions can contain functions and computed/constant get variables. They are in the format extension ExtensionOf { //new functions and get-variables } To reference the instance of the extended object, self can be used, just as it could be used To create an extension of String that adds ...

Extensions can contain convenience initializers. For example, a failable initializer for Int that accepts a NSString: extension Int { init?(_ string: NSString) { self.init(string as String) // delegate to the existing Int.init(String) initializer } } let str1: NSString = &qu...

import operator reduce(operator.mul, [10, 5, -3]) # Out: -150

reduce will not terminate the iteration before the iterable has been completly iterated over so it can be used to create a non short-circuit any() or all() function: import operator # non short-circuit "all" reduce(operator.and_, [False, True, True, True]) # = False # non short-circu...

# First falsy element or last element if all are truthy: reduce(lambda i, j: i and j, [100, [], 20, 10]) # = [] reduce(lambda i, j: i and j, [100, 50, 20, 10]) # = 10 # First truthy element or last element if all falsy: reduce(lambda i, j: i or j, [100, [], 20, 0]) # = 100 reduce(la...