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A Distributed solution to /r/dailyprogrammer Challenge #223

A little while ago, I wrote my first distributed computing program to solve the second optional challenge to /r/dailyprogrammer's #223rd problem. I wrote it in Javascript, because I know really know how to utilise the tcp/ip networking stack in any other language yet :(

Anyway, if you want to check out my source code, I have put it up on GitHub. Below I will explain how you can get started with the pair for scripts I wrote, and how they work

Getting Started

Getting started is easy. Just clone the repository & cd into the new directory:

git clone
cd dailyprogrammer-223

Then install the dependency:

npm install

Then you can start a server like so:

node server.js 4321 # starts a new server on port 4321

Or you can start a client like this:

node client.js

Note that I have used some ES6 features (check out my ES6: Features series), so if you are using Node.js and not io.js, you will need to tack on the --harmony flag in order to get them to work.

It works by mapping the search space (aaaaa to zzzzz) to a set of numbers, starting at 0. I used an ES6 generator to keep track of where we have got up to, wrapped in a function that handles reallocating work units that haven't been completed within a certain time limit. Each work unit consist of 16 words by default (though it can be changed), with the time limit set to 5 times the number of words in the block.

Next time, I will write the client so that it is compatible with a conventional browser - this should make it much easier for people to contribute their CPU time!

Dailyprogammer Challenge #199 - Bank Numbers Pt 1

I have attempted another dailyprogammer challenge on reddit.

This time, the challenge is to take a number in and print a 'banner' representing that number, like this:

Input: 47262

    _  _  _  _
|_|  | _||_  _|
  |  ||_ |_||_

Here is my solution:

using System;

public class BigDigits
    static string[,] bannerTemplates = new string[,]{
        { " _ ", "| |", "|_|" },
        { "   ", "  |", "  |" },
        { " _ ", " _|", "|_ " },
        { " _ ", " _|", " _|" },
        { "   ", "|_|", "  |" },
        { " _ ", "|_ ", " _|" },
        { " _ ", "|_ ", "|_|" },
        { " _ ", "  |", "  |" },
        { " _ ", "|_|", "|_|" },
        { " _ ", "|_|", " _|" }

    static void Main(string[] args)
        if (args.Length == 0)
            Console.WriteLine("This program converts a number to a banner.");
            Console.WriteLine("\nUse it like this: ");
            Console.WriteLine("    bigintbanners.exe <number>");
            Console.WriteLine("\n<number>: The number you want to convert.");

        char[] intChars = args[0].ToCharArray();
        string[] resultLines = new string[3];
        int currentDigit = 0;

        int i = 0;

        for(i = 0; i < intChars.Length; i++)
            currentDigit = int.Parse(intChars[i].ToString());
            for (int j = 0; j < 3; j++)
                resultLines[j] += bannerTemplates[currentDigit,j];

        for(i = 0; i < resultLines.Length; i++)

I find the dailyprogrammer challenges to be a great way to practice a language that you are learning.

32 bit binary, SHA1: 0fc2483dacf151b162e22b3f9b4c5c64e6fe5bdf

Reddit post link

Ask below if you need a different binary (e.g. 64 bit, ARM, etc)

Dailyprogrammer challenge #197 - Validating ISBN Numbers

Hello again!

I now have a reddit account. You can find it here:

I have attempted the latest Daily Programmer challenge.

This time I have written it in javascript. The challenge was to validate an ISBN-10 number. To validate an ISBN-10 number, you add 10 times the first number to 9 times the second number to 8 times the third number and so on. This total should leave no remainder when divided by 11. In addition, the letter X stands for a value of 10.

Here is my solution:

function validate_isbn(isbn) {
    var i = 10,
        tot = isbn.replace(/-/g, "").split("").reduce(function (total, char) {
            if (char.toLowerCase() == "x")
                total += i * 10;
                total += i * parseInt(char);
            return total;
        }, 0);

    if (tot % 11 === 0)
        return true;
        return false;

I minified it by hand too:

function validate_isbn(a){var i = 10;if(a.replace(/-/g,"").split("").reduce(function(b, c){if(c.toLowerCase()=="x")b+=i*10;else b+=i* parseInt(c);i--;return b;},0)%11==0)return true;else return false;}

I should probably attempt the next challenge in C♯ so that I keep practising it.

The daily programmer challenge can be found here: Daily Programmer Challenge #197 - ISBN Validator

Art by Mythdael