Pancake Sort is a the colloquial term for the mathematical problem of sorting a disordered stack of pancakes in order of size when a spatula can be inserted at any point in the stack and used to flip all pancakes above it. A pancake number is the minimum number of flips required for a given number o...
public class PancakeSort
{
private static void SortPancake(int[] input, int n)
{
for (var bottom = n - 1; bottom > 0; bottom--)
{
var index = bottom;
var maxIndex = input[bottom];
int i;
for (i = bottom - 1; i >= ...
The Caesar cipher is a classic encryption method. It works by shifting the characters by a certain amount. For example, if we choose a shift of 3, A will become D and E will become H.
The following text has been encrypted using a 23 shift.
THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG
QEB NRFZH YOL...
The ASCII way
This shifts the characters but doesn't care if the new character is not a letter. This is good if you want to use punctuation or special characters, but it won't necessarily give you letters only as an output. For example, "z" 3-shifts to "}".
def ceasar(text, shi...
ROT13 is a special case of Caesar cipher, with a 13 shift. Only letters are changed, and white-space and special characters are left as they are.
What is interesting is that ROT13 is a reciprocal cipher : applying ROT13 twice will give you the initial input. Indeed, 2 * 13 = 26, the number of lette...
To connect to a mongo database from node application we require mongoose.
Installing Mongoose
Go to the toot of your application and install mongoose by
npm install mongoose
Next we connect to the database.
var mongoose = require('mongoose');
//connect to the test database running on defau...
With Mongoose, everything is derived from a Schema. Lets create a schema.
var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var AutoSchema = new Schema({
name : String,
countOf: Number,
});
// defining the document structure
// by default the collection...
For inserting a new document in the collection, we create a object of the schema.
var Auto = require('models/auto')
var autoObj = new Auto({
name: "NewName",
countOf: 10
});
We save it like the following
autoObj.save(function(err, insertedAuto) {
if (err) return cons...
For updating collections and documents we can use any of these methods:
Methods
update()
updateOne()
updateMany()
replaceOne()
Update()
The update() method modifies one or many documents (update parameters)
db.lights.update(
{ room: "Bedroom" },
{ status: "On&quo...
Deleting documents from a collection in mongoose is done in the following manner.
Auto.remove({_id:123}, function(err, result){
if (err) return console.error(err);
console.log(result); // this will specify the mongo default delete result.
});
To call a list of goals as if it were a conjunction of goals, combine the higher-order predicates call/1 and maplist/2:
?- Gs = [X = a, Y = b], maplist(call, Gs).
Gs = [a=a, b=b],
X = a,
Y = b.
systemd provides a modern implementation of cron. To execute a script periodical a service and a timer file ist needed.
The service and timer files should be placed in /etc/systemd/{system,user}.
The service file:
[Unit]
Description=my script or programm does the very best and this is the descri...
Detailed instructions on getting slick set up or installed.
http://kenwheeler.github.io/slick/
Slick Slider is easy to use and to customise. It provides good amount of customisation options including responsive options based on breakpoints.
To get started with slick, it is not that difficult. Jus...
C#
Visual Studio 2015 (latest update) - you can download the community version here for free: www.VisualStudio.com
Important: update all VS extensions to their latest versions
Tools->Extensions and Updates->Updates
Download the Bot Application template from here: Template Dow...
Below is an example of Gstreamer pipeline embedded in a simple gtk window. When run, a small window should appear like this:
import gi
gi.require_version('Gtk', '3.0')
gi.require_version('Gst', '1.0')
from gi.repository import Gtk, Gst
Gst.init(None)
Gst.init_check(None)
class GstWidg...
Below is a configuration file for log4j. Log4j2 can use the same syntax, but there are different appender classes:
log4j.rootLogger=INFO, FOO
## ConsoleAppender
log4j.appender.CA=org.apache.log4j.ConsoleAppender
log4j.appender.CA.layout=org.apache.log4j.PatternLayout
log4j.appender.CA.layout....
XML Example
The below configuration configures two appenders (log output). The first logs to standard system output (console) and the other logs to file. In this example, the location of the file can be set statically in configuration (appender file) or dynamically via maven filtering feature (<...
Recursive functions can get quite expensive. If they are pure functions (functions that always return the same value when called with the same arguments, and that neither depend on nor modify external state), they can be made considerably faster at the expense of memory by storing the values already...
There are different variable types for different purposes. In Visual Basic 6 the following variable types are available:
Array
Boolean
Byte
Currency
Date
Double
Integer
Long
Single
String
Variant
You declare a variable by using the Dim keyword:
Dim RandomNumber As Integer
If you ...
