Synacor Challenge

This project is a usual CLI application written in Rust. It also contains additional folders:

• data contains the executable binary for Virtual Machine and script with the full list of commands to complete the challenge
• playground contains tiny CLI apps that were written during solving quest's tasks

Virtual Machine

The whole challenge is messing around with a virtual machine. In the very beginning, you should implement 22 instructions according to the architecture specifications. That's not sound like a pretty complex task but it requires a accuracy in this routine.
Once the virtual machine is completed, you may start it and play the text-based adventure game. Hello from 80th)

The Adventure Game

Make sure that Cargo and Rust are installed. Then execute in your command line

cargo run -- data/challenge.bin

Coins

The bruteforce solution to order the coins is here

Teleporter

I needed to write a disassembly and execution dump for the virtual machine to obtain the entry point, conditions to activate the handheld teleporter, and bypass its confirmation mechanism. There is a separate branch for that purpose. The result is looks something like this:

5483          set [r0] 4
5486          set [r1] 1
5489         call @6027
6027           jt [r0] @6035
6030          add [r0] [r1]  1
6034          ret
6035           jt [r1] @6048
6038          add [r0] [r0]  32767
6042          set [r1] [r7]
6045         call @6027
6047          ret
6048         push [r0]
6050          add [r1] [r1]  32767
6054         call @6027           
6056          set [r1] [r0]       
6059          pop [r0]
6061          add [r0] [r0]  32767
6065         call @6027           
6067          ret

The search for valid value for the 8th register is here. The virtual machine patches the program before execution to pass the confirmation mechanism and, of course, to obtain the valid next challenge code.
Actually, this is an Ackermann function

Vault

You need to change the orb's weight from 22 to 30 by moving among the rooms. The path should be the shortest. The backtracking search for this task is here. It isn't a brilliant implementation but good enough to pass this task and complete the challenge.

Whole challenge

This is a great spoiler on how to pass the challenge and obtain all codes (except the first one):

cargo run -- data/challenge.bin data/script.txt

Enjoy)