What's the most beautiful code you've ever written? By beautiful I mean simple, clean, and implementation of a potentially complex function/algorithm.
I wrote a Turing machine in a version of Turtle Art made of snap-together programming blocks for the purpose of teaching Computer Science concepts to elementary school students in the One Laptop Per Child program. I coded the symbols on the Turing machine tape as colored dots which the turtle could read and translate to integers used as indices into the program table. The table was also made of dots that the turtle could read to determine what state to go into what symbol to write on the tape and which way to move the head for the next iteration. The initial state of the tape for the simple addition 3+2 math appears on the top edge and the program table below. At the end of execution for this simple case when the machine halts we get the tape state containing the answer and also an execution trace as shown below. Activities Art Art Turing Machine s Here are pictures of theplete code with annotations. Activities Art Art Code for Turing Machine s I also provided a machine translation into Logo on a separate page ed from those above. Inparison with -basedputer languages this kind of Turtle Art makes most typing and syntax errors impossible. The user programs directly in a tree structure a much more natural CS representation of a program than a that has to go through lexical analysis and parsing stages to get to a parse tree. On a larger scale I rmend a number of elegant programming language implementations that an undergraduate could read in their entirety including the original Pure LISP the original FORTH Smalltalk and J Ken Iverson's last version of APL. Some of them have implementations written entirely in their own languages with a kernel that can be crosspiled to any new architecture.
What do you think about the recent malware attack (ransome)?
I think its very harsh. If youve done your best to stay away offline for the past two days so you could actually enjoy your weekend you undoubtedly now find yourself trying to catch up on all the news surrounding WannaCry ransomware. What is ransomware? First and foremost let clarify exactly what italic WannaCry italic is. This malware is a scary of trojan virus called italic ransomware. italic As the name suggests the virus in effect holds the infectedputer hostage and demands bitcoins that the victim pay a ransom in order to regain access to the files on his or herputer. italic What it exactly do when it entered in your Windows PC. Yeah Here its the process after affecting - RansomWare italic like WannaCry italic works by encrypting most or even all of the files on yourputer. Then the software demands that a ransom be paid in order to have the files decrypted. In the case of WannaCry specifically the software demands that the victim pays a ransom of $3 in bitcoins at the time of infection. If the user doesn pay the ransom without three days the amount doubles to $6. After seven days without payment WannaCry will delete all of the encrypted files and all data will be lost. Per Symantec here is a full list of the files that are targeted and encrypted by WannaCry .123 .3dm .3ds .3g2 .3gp .62 .7z .ARC .accdb .aes .ai .asc .asf .asm .asp .avi .backup .bak .bat .bmp .brd .bz2 .cgm .cmd .class .cpp .crt .cs .csr .csv .db .dbf .dch .der .dif .dip .djvu .doc .docb .docm .docx .dot .dotm .dotx .dwg .edb .eml .fla .flv .frm .gif .gpg .gz .hwp .ibd .iso .jar .java .jpeg .jpg .js .jsp .key .lay .lay6 .ldf .m3u .m4u .max .mdb .mdf .mid .mkv .mml .mov .mp3 .mp4 .mpeg .mpg .msg .myd .myi .nef .odb .odg .odp .ods .odt .onetoc2 .ost .otg .otp .ots .ott .p12 .pas .pdf .pem .pfx .php .pl .png .pot .potm .potx .ppam .pps .ppsm .ppsx .ppt .pptm .pptx .ps1 .psd .pst .rar .raw .rb .rtf .sch .sh .sldm .sldx .slk .sln .snt .sql .sqlite3 .sqlitedb .stc .std .sti .stw .suo .svg .swf .sxc .sxd .sxi .sxm .sxw .tar .tbk .tgz .tif .tiff .txt .uop .uot .vb .vbs .vcd .vdi .vmdk .vmx .vob .vsd .vsdx .wav .wb2 .wk1 .wks .wma .wmv .xlc .xlm .xls .xlsb .xlsm .xlsx .xlt .xltm .xltx .xlw .zip Do you think Attack is over? Big NOOOOOOO italic WannaCry was first discovered on Friday May 12th and it had spread to an estimated 57puters in more than 15 different countries around the world by the end of the day. European countries were hit the hardest and business ground to a halt at several largepanies and organizations including banks hospitals and government agencies. On Saturday a 22-year-old security researcher named Marcus Hutchins inadvertently slowed the spread of the WannaCry virus when he registered a domain name hidden within the virus code in an attempt to track the spread of WannaCry unintentionally stopping its progress in the process. You can read Hutchins story in his blog post titled How to Accidentally Stop a Global Cyber Attacks. italic Protect yourputers from this stuff Regardless of which operating system you run you should install any and all available security updates immediately. Specifically Windows users with machines that run Windows XP Windows 8 or Windows Server 23 should immediately install this security update s released on Friday by Microsoft. Thanks )
How can I upload scripts to Dropbox in text files?
What is ransomware?
Ransom malware or directly ransomware attack is a of malware that blocks users from accessing their system or personal files and requires a ransom payment to regain access. The earliest variants of ransomware software were developed in the late 198s and the amount was to be sent by snail mail. Today authors of ransomware require payment to be sent via cryptocurrency or credit card. How the ransomware works There are several ransomware vectors that they can download to access aputer. One of the mostmon delivery systems is spam phishing - plugins that reach the victim via email disguising themselves as a file they need to trust. Once downloaded they can download the victim'sputer - if they have built-in social engineering tools that torture users to allow administrative access. Who is a target for ransomware? There are several different ways attackers choose the organizations that target them with ransomware software. Sometimes this is a matter of opportunity attackers may for example target universities because they tend to have smaller security teams and a different user base that does a lot of file sharing which facilitates penetration into their defense. On the other hand some organizations are adopting lucrative goals because they seem to be more likely to pay off the ransom quickly. On the instance government agencies or medical facilities often need immediate access to their files. Lawyers and other organizations with sensitive data may be willing to pay to silence news ofpromise - and these organizations may be uniquely vulnerable to leak attacks. Types of ransomware There are three certain known s of ransomware Scareware The scarf it turns out is not that daunting. Includes rogue security software and support technology scams. You may receive a popup message claiming that malware has been discovered and the only way to get rid of it is to pay. If you do nothing you will probably continue to be bombarded with popups but your files are inherently safe. Screen lockers Upgrade to the orange alert for these guys. When Ransomware appears on yourputer lock screen it means that you are entirely frozen from yourputer. When starting yourputer a full-size window will appear often apanied by an official FBI or US Department of Justice press release saying illegal activity has been detected on yourputer and you must pay a fine. However the FBI does not freeze you from yourputer or require payment for illegal activity. If you suspect piracy child pornography or other network crimes they will go through the appropriate legal channels. Encrypting Ransomware It is a nasty thing. These are guys who grab your files and encrypt them demanding payment to decrypt and redo them. The reason why this of ransom is so dangerous is that once the cyber-criminals have retained your files no security software or system recovery can bring them back to you. Unless you pay a ransom - for the most part they aren't. And even if you get paid there is no guarantee that cybercriminals will get these files back to you. To learn more about Mac ransomware please visit this post s .