Nikhil M niksmac

Describe why it’s hard to code a random number generator in Ethereum. Summarize a few reasons why most intuitive solutions fail (eg. getting from block number)
Describe an efficient approach to using off-chain data in an ethereum contract that minimizes the amount of trust required.
Create an efficient solidity contract that includes the following functions:

sqrt(uint x) that returns the square root of a number to 2 decimal places
selectionsort(uint[] x) that uses the selection sort algorithm to return a sorted array
factorial(int x): returns the factorial of x using recursion

Random color from string in javascript

Consider a list of strings you need to permanently assign a random color.

First you should turn the string into a hash.

var string = "string"
var hash = 0

File view `5`

a - add file/folder

Library view `2`

c - play / pause

v - stop

Profiling an application in Mac OS X

Finding which process to profile

If your system is running slowly, perhaps a process is using too much CPU time and won't let other processes run smoothly. To find out which processes are taking up a lot of CPU time, you can use Apple's Activity Monitor.

The CPU pane shows how processes are affecting CPU (processor) activity:

Markdown-Writer for Atom

List all posts, tags and categories in Jekyll.

Octopress users: if you found " is escaped in the generated JSON file, please change them to \". Refer to this issue.

Architecture in Elm

This document is a collection of concepts and strategies to make large Elm projects modular and extensible.

We will start by thinking about the structure of signals in our program. Broadly speaking, your application state should live in one big foldp. You will probably merge a bunch of input signals into a single stream of updates. This sounds a bit crazy at first, but it is in the same ballpark as Om or Facebook's Flux. There are a couple major benefits to having a centralized home for your application state:

There is a single source of truth. Traditional approaches force you to write a decent amount of custom and error prone code to synchronize state between many different stateful components. (The state of this widget needs to be synced with the application state, which needs to be synced with some other widget, etc.) By placing all of your state in one location, you eliminate an entire class of bugs in which two components get into inconsistent states. We also think yo

Creating PDF thumbnails in PHP

Install Ghostscript

Download and install right version of ghostscript. In my case my PHP was x86 architecture, so I download Ghostscript 9.14 for Windows (32 bit).

	/**
	* Base contract that all upgradeable contracts should use.
	*
	* Contracts implementing this interface are all called using delegatecall from
	* a dispatcher. As a result, the _sizes and _dest variables are shared with the
	* dispatcher contract, which allows the called contract to update these at will.
	*
	* _sizes is a map of function signatures to return value sizes. Due to EVM
	* limitations, these need to be populated by the target contract, so the
	* dispatcher knows how many bytes of data to return from called functions.

	module Dropdown where

	import List exposing (..)
	import Html exposing (..)
	import Html.Attributes exposing (style)
	import Html.Events exposing (onClick, onBlur)


	-- MODEL

	<?php
	function SetPerms($dir = ".") {
	$listDir = array();
	if($handler = opendir($dir)) {
	while (($sub = readdir($handler)) !== FALSE) {
	if ($sub != "." && $sub != "..") {
	if(is_file($dir."/".$sub)) {
	echo "File: $dir/$sub\n";
	chmod($dir."/".$sub, 0644);