jin

def check_string(str)
  str.empty? || is_balanced(0, str)
end

def is_balanced(num_left_brackets, str)
  if str.head == "["
    is_balanced(num_left_brackets + 1, str.tail)
  elsif str.head == "]" 
    return false if num_left_brackets == 0
    is_balanced(num_left_brackets - 1, str.tail)

jin

class Array
  def reduce(func, init)
    if self.length < func.arity
      res = nil
    elsif self.length == func.arity
      res = func.call(*self)
    else
      res = func.call(self[0], self[1..-1].reduce(func, nil))
    end
    init.nil? ? res : func.call(init, res) 

jin

#!/usr/bin/env ruby

def sum_of_differences(arr)
  total = 0
  arr.each_cons(2) do |x, y|
    total += (x - y).abs
  end
  total
end

jin

# Regular Ruby methods, can't pass them around like function objects

def length(xs)
  return 0 if xs.empty?
  1 + length(xs[1..-1])
end

def map(xs, process = -> (x) { x })
  return [] if xs.empty?
  [process.call(xs.first)] + map(xs[1..-1], process)

jin

def sort hash
  hash.keys.map(&:to_s).sort(& -> (a, b) { a.length <=> b.length })
end

p sort ({ abc: 'hello', 'another_key' => 123, 4567 => 'third' })

jin

Node = Struct.new(:val, :next_node) do

  def length
    return 1 if next_node.nil?
    1 + next_node.length
  end

  def to_s
    self.to_a.join(", ")
  end

jin

# A USB tether always make use of the 3G/4G connection of your iPhone.
# You can override this config by buying MyWi 8.0 for 20 bucks or
# do the following. :-)

# Skip to step 4 if you already have ssh set up.

# 1) Install OpenSSH from Cydia
# 2) ssh into your phone. default password is `alpine`.
# I use CCSystemInfo to access my iPhone's cellular IP address easily.

jin

Keybase proof

I hereby claim:

• I am jin on github.
• I am jin (https://keybase.io/jin) on keybase.
• I have a public key whose fingerprint is 124B CC2E 008C 650E FF3D EC71 47D0 E655 F065 B791

To claim this, I am signing this object:

jin

/****************************************************************
 *	Sudoku Solver
 *
 *	Translated into Javascript from original code in C++
 *		by Lee Hsien Loong
 *	The MIT License (MIT)
 *	Copyright (c) 2015 Vivian Balakrishnan
 *
 *
 ****************************************************************/

jin

require 'nokogiri'
require 'httparty'
require 'concurrent'
require 'pp'

class HWZRequest

  def initialize
    @host = "http://forums.hardwarezone.com.sg"
  end