itismadhan

class JsonHelper {
    class func JSONStringify(jsonObj: AnyObject) -> String {
        var e: NSError?
        let jsonData: NSData! = NSJSONSerialization.dataWithJSONObject(
            jsonObj,
            options: NSJSONWritingOptions(0),
            error: &e)
        if e != nil {
            return ""
        } else {

itismadhan

Implementing a Reverse Polish notation calculator in Ruby

A couple weeks ago I had a go at implementing an RPN calculator in Ruby. I knew I wanted the calculator to function by popping operands out of an array populated with the values of the input expression, operating upon the operands with the appropriate operator, and pushing the result back into the stack of operands.

I was able to implement this in version 1, but it took forever and the resulting code was not very beautiful. Why?

• I started coding before I had a thorough understanding of RPN

  Wait, 20 10 5 4 + * - is what now?

itismadhan

list = [1, 2, 5, 7, 20]
def check_sum list
  list_hash = Hash.new
  list.each do |item|
    if list_hash.has_key?(10-item)
      return true
    else
      list_hash[item] = true
    end
  end

itismadhan

# You will need the pygments and xclip packages
# This example highlights some Bash source code
# '-O noclasses=true' tells pygments to embed colors inline in the source
# the '-t text/html' option tells xclip what "target" to specify for the selection
pygmentize -l bash -f html -O noclasses=true mysource.sh | xclip -selection clipboard -t text/html

itismadhan

#!/usr/bin/env ruby
# 2011-10-10 20:57:53 +1000

def merge_sort(a)
    return a if a.size <= 1
    l, r = split_array(a)
    result = combine(merge_sort(l), merge_sort(r))
end

itismadhan

#!/usr/bin/env ruby
# 2011-10-10 20:57:53 +1000

def merge_sort(a)
    return a if a.size <= 1
    l, r = split_array(a)
    result = combine(merge_sort(l), merge_sort(r))
end

itismadhan

module BinaryTree
  class Node
    attr_reader :word, :count, :left, :right

    include Enumerable

    def initialize(word)
      @word, @count = word, 1
    end

itismadhan

# Depth-first search (DFS) is an algorithm for traversing or
# searching a tree, tree structure, or graph. One starts at 
# the root (selecting some node as the root in the graph case)
# and explores as far as possible along each branch before backtracking.
#
# A graph can be represented by its adjacency matrix G,
# where G[i][j] == 1 if there is an edge between 
# vertices i and j and 0 otherwise.
#
# Below Graph in diagram http://i.imgur.com/sV1UzUn.png