CryptRandom puzzle

[firace]

See the below snippet.
I'm not able to figure out why total is not equal to 6000, but sometimes higher, and sometimes lower ? Am I off by one somewhere? (PB 5.31, Windows 8.1, 32-bit)

Note: I created balancedCryptRandom() so that a power of 2 minus 1 is always passed to CryptRandom(), as per the help file.

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OpenCryptRandom()
procedure balancedCryptRandom(x)    
  j=1
  repeat :  j*2  :  until j>x  
  
  Repeat
    dice = CryptRandom(j-1) + 1
  Until dice <= x
  
  ProcedureReturn dice
  
EndProcedure


dim results(6)
for i=1 to 6000
  results(balancedCryptRandom(6)) + 1 
;   jj + 1
next

for i=1 to 6
  debug "Value " + i + " occurred: " + results(i) + " times."
  
  total + results(i)
next

debug total
; debug jj

[Sirius-2337]

The problem is this line:

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results(balancedCryptRandom(6)) + 1

It is only a shortcut and will be expanded to this line by the compiler:

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results(balancedCryptRandom(6)) = results(balancedCryptRandom(6)) + 1

Now you see the problem I guess.

You need to write it like this:

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a = balancedCryptRandom(6)
  results(a) + 1

[firace]

Awesome! Great explanation, thanks.