johnhaitas

Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

Array

Definition:

• Stores data elements based on an sequential, most commonly 0 based, index.
• Based on tuples from set theory.

johnhaitas

#!/bin/sh

#  insert_git_hash.sh
#  ToGoOrder
#
#  Created by John Haitas on 7/9/13.
#

# Location of Info.plist in build product
INFOPLISTPATH="${TARGET_BUILD_DIR}/${EXECUTABLE_NAME}.app/Info.plist"

johnhaitas

#!/bin/sh

#  insert_git_hash.sh
#  ToGoOrder
#
#  Created by John Haitas on 7/9/13.
#

# Location of Info.plist in build product
INFOPLISTPATH="${TARGET_BUILD_DIR}/${EXECUTABLE_NAME}.app/Info.plist"

johnhaitas

#!/bin/sh

#  insert_git_hash.sh
#  ToGoOrder
#
#  Created by John Haitas on 7/9/13.
#

# Location of Info.plist in build product
INFOPLISTPATH="${TARGET_BUILD_DIR}/${EXECUTABLE_NAME}.app/Info.plist"

johnhaitas

[aDictionary objectForKey:@"Key"] -> aDictionary[@"Key"]
=========================================================

Find
\[(\w+) *objectForKey: *(@"\w+") *\]

Replace
\1\[\2\]

johnhaitas

"_fnDetectBrowser": function ()
{
	var ua = navigator.userAgent.toLowerCase();

	// userAgent RegExp
	var rwebkit  = /(webkit)[ \/]([\w.]+)/,
	    ropera   = /(opera)(?:.*version)?[ \/]([\w.]+)/,
	    rmsie    = /(msie) ([\w.]+)/,
	    rmozilla = /(mozilla)(?:.*? rv:([\w.]+))?/,
	    rsafari  = /(safari)[ \/]([\w.]+)/,

johnhaitas

if ( !$.browser.mozilla )
{
	// Bind 'scroll' for most browsers
} else {
	// Bind 'scroll' for Mozilla browsers
}

if ( $.browser.safari )
{
	// Bind 'mousewheel' for Safari

johnhaitas

#!/usr/bin/perl
use File::Find;

my $backup_root = "/path/to/folder"

# purge backups older than AGE in days
my @file_list;
my @find_dirs       = ($backup_root);           # directories to search
my $now             = time();                   # get current time
my $days            = 30;                       # how many days old

johnhaitas

a='o'*12
a[gets.to_i%12]=?h
a[m=$_[3,2].to_i/5]=a[m]<?o??x:?m
b=Array.new(11){" "*17}
12.times{|i|t=i*0.523-1.57;b[(5+4.9*Math.sin(t)).round][(8+8*Math.cos(t)).round]=a[i]}
b.map{|l|puts l.rstrip}

johnhaitas

def neighbors(cell)
  neighbors = []
  x = cell[0]
  y = cell[1]
  (x-1..x+1).each do |xx|
    (y-1..y+1).each do |yy|
     next if xx==x && yy==y
     neighbors.push([xx,yy])
    end
  end