Will it halt? (Robbers) This is the robbers' thread. The cops' thread is here.

Your challenge is to crack a cop's submission by finding an input that makes it halt. You don't have to find out why, or all inputs that make it halt if there's more than one, or the input the cop intended, just one input will do.

Once you have cracked a submission, post a link to it in a comment or edit to the cop's post. You can also flag your submission for a mod to edit it in the cop's post. Also, post the input used and a link to the cop's post in an answer in this thread. The robber that cracks the most submissions wins.

Multiple people can post cracks to the same cop submission, as long as they are different.

(If SE converted your duplicate answer to a comment, you may want to vote on this feature request)



Looking for uncracked submissions?



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Malbolge, Doorknob

Try it online (Thanks Dennis!)

Input for Windows: F_⌠1234567890

Input on Linux based system using ISO-8559-1: F_ô1234567890

The heart of how the Malbolge program worked is that it depended on a behavior of the Malbolge interpreter which causes an infinite loop if it encounters any instruction which is not between 33 and 126. The program was constructed such that your input would allow you to modify a single instruction.

I modified the interpreter to dump the program memory state at the beginning of execution and to also produce 'normalized' source code which takes the form of a list of op codes that will be run during the execution of the program. With that information you could (slowly) determine that even though the program took 
 13 inputs only the 1st and 3rd inputs actually mattered.

Looking through the normalized code and memory dump (and a touch of debugger help) I devised the following:


  a = op(input 1, 29524)
  
  b = op(input 3, a)
  
  c = op(486, b)
  
  d = op(c, 37)
  
  e = d/4 + d%3 * 3^9
  
  e must be between 33 and 126


Where op is the so called tritwise "op" that is described in the specification. Using this information you can write a simple program which iterates over the possible inputs (0 to 255) and finds all solutions which meet the above criteria. I had found 2219 possible solutions, some of which will probably not be working solutions (you can't input the required characters). Specifically the above inputs are based on the solution: 

(Input 1 = 70, Input 3 = 244)