Two Makes All The Difference - Cops

Cracked

Shakespeare, 1721 bytes

I tried a Shakespeare answer. It is not short, and I had difficulties to change the output with only 2 characters, but I think I succeeded quite well. Good Luck everybody. As a side note, I used the "compiler" available at this address and it may not work with another one. (it does not work with the online interpreter) The output does not contain any unprintable characters.

Code

The Hidden Change.

Helen, a young woman with a remarkable patience.
Helena, a likewise young woman of remarkable grace.
Claudio, a remarkable man much in dispute with Claudius.
Claudius, the flatterer.
The Archbishop of Canterbury, the useless.


          Act I: Claudius's insults and flattery.

          Scene I: The insulting of Helen.

[Enter Claudius and Helen]

Claudius:
 Thou art as hairy as the sum of a disgusting horrible fatherless 
 dusty old rotten fat-kidneyed cat and a big dirty cursed war.
 Thou art as stupid as the product of thee and a fat smelly 
 half-witted dirty miserable vile weak son.
 
[Exeunt]

          Scene II: The complimenting of Helena.
          
[Enter Claudio and Helena]

Claudio:
 Thou art the sunny amazing proud healthy peaceful sweet joy.
 Thou art as amazing as the product of thee and the pretty
 lovely young gentle handsome rich Hero. Thou art as great 
 as the sum of thee and the product of a fair golden prompt good honest 
 charming loving noble king and a embroidered rich smooth golden angel.
 
[Exeunt]

          Scene III: The insulting of Claudio
          
[Enter Claudius and Helen]

Helen:
 Thou art as stupid as the sum of the sum of thee and a cat and me.
[Exit Helen]

[Enter Claudio]

Claudius:
 Thou art as stupid as the sum of thee and the product of the 
 product of me and Helen and Helena
 
[Exeunt]

          Scene IV: The Final Countdown
          
[Enter The Archbishop of Canterbury and Claudius]

Claudius:
 Thou art the sum of you and a cat.

The Archbishop of Canterbury:
 Am I better than a fine road?
 
Claudius:
 If not, let us return to the insulting of Claudio.
 
[Exit The Archbishop of Canterbury]

[Enter Claudio]

Claudius:
 Open your heart!
 Open your heart!
[Exeunt]

Original Output

11324620811132462081

Changed Output

11

J, 76 bytes (safe)

Code

,:|.,.<,:>><|.,:>,.<|.>,:<<|.>|.,:,.<,.<,:,.<,:>|.<,:>,.|.<,:,.|.<<,:>126$a.

Original Output

┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
│┌────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐│
││┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐││
│││┌────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐│││
││││┌──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┐││││
│││││     ┌┬┐├┼┤└┴┘│─ !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_`abcdefghijklmnopqrstuvwxyz{|}│││││
││││└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘││││
│││└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘│││
││└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘││
│└────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘│
└──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────┘

Changed output

┌──────────────────────┐
│┌────────────────────┐│
││┌──────────────────┐││
│││┌────────────────┐│││
││││┌──────────────┐││││
│││││┌───────────┬┐│││││
││││││0 0 0 0 0 0│││││││
│││││└───────────┴┘│││││
││││└──────────────┘││││
│││└────────────────┘│││
││└──────────────────┘││
│└────────────────────┘│
└──────────────────────┘

EDIT: Solution {: added (shown between ###)

,:|.,.<,:>><|.,:>,.<|.>,:<<|.>|.,:,.<,.<,:,.<,###{:###:>|.<,:>,.|.<,:,.|.<<,:>126$a.

Makes use of the monad {:: Map. Most of the rest of the code is useless garbage.

Cracked

Ruby, 14

Code

x=9;puts x*9*9

Original Output

729

Changed output

99999999999999999