Welcome to HBH! If you have tried to register and didn't get a verification email, please using the following link to resend the verification email.

The concept behind Timed 7


The concept behind Timed 7

By elmiguel avatarelmiguel | 9248 Reads |
0     0

“The challenge is to crack the barcode. Post the barcode number (id is barcode) and whether the barcode is 'valid' or 'invalid' (id is validity) to this page. Make sure to handle your cookies properly. Good Luck!”

Wow, this seems extremely hard. It really isn’t that hard to accomplish. In this article I will NOT show you how to beat this challenge, but I WILL show you the concept behind this challenge. This will enable you to write you own code in any language of your choosing.

The most important thing you need to do is figure out the complete operation of this challenge. First, write out either on paper or in an editor out the steps of what you are trying to do. For example:

Barcode Decoder Script 1: Load libraries/modules to make the connection, process images, and so on. 2: State initial variables. 3: Make the connection. 4: Download Image / Save to folder 5: Open Image locally. 6: Analyze image 7: Grab the data / Calculate Barcode Image. 8: Decode / Covert data. 9: Post back the data.

Second, write out the script. Once you have the most direct plan of attack, write it out as best as you can. Be sure to test the script as often as possible. It is good practice to test out the script after every line added or changed to see it is working correctly. When writing out your code, think about what is going on and how to make it work for you. If some code is not working exactly the way you want it to, take a step back and see why it is working that way. Most of the time, you may be using the code the wrong way.

Finally, once you made all your calculations all that is left to do is post back your answer to the web page.

When doing this challenge you have to do a lot of research. I will give to some key points to think about that will help you in your research. Figure out how the barcode works and how to decode it. Figure out what code type the barcode is this is very important because there are a few are close. You will know which one after read about a few different code types. Hint: Think back to basic web hacking one that should help you get started. Once you have figured out the barcode code type and how to decode it make sure you understand that barcodes can be read from left to right and/or right to left. This will help you when you are writing your conversion function. The last key point would be to make sure you understand what the id’s are when making you post. For instance, &Key1=‘value’&Key2=‘value’.

-elmiguel

Comments
GTADarkDude's avatar
GTADarkDude 15 years ago

Timed 7 was one of the challenges I liked most on this site. It is one of those challenges that look hard on first sight, but when doing a bit of puzzling appear to be rather easy. Therefore I can't really see why this challenge in particular needs an article that is meant to help others. For the rest of it, I agree with Mosh. Too little information that actually helps others ands too much useless, empty sentences. Well, (just to say something good,) at least you (slightly) understand punctuation and paragraphs.