SERVING THE QUANTITATIVE FINANCE COMMUNITY

 
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player
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Posts: 2290
Joined: August 5th, 2002, 10:00 am

pin number

November 12th, 2010, 12:54 pm

a pin number has four numbers. How long does it take to break it using brute force?
 
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Traden4Alpha
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Joined: September 20th, 2002, 8:30 pm

pin number

November 12th, 2010, 1:31 pm

If "brute force" means punching the card holder in the mouth a few times, then not long. If all four digits can take on any of 10 values (0-9) and pins are random, then it takes an average of 10000/2 tries.If all four digits can take on any of 10 values (0-9) and pins are human-created, then it takes less time if I have access to a database of human-created pin numbers (such a database might reveal that "1234" is an extremely common pin number).If I don't have to enter all 4 digits -- unentered digits resolve as leading or trailing zeros (e.g. "1 ENTER" == "1000 ENTER") then 999+99+9 of my tries will require fewer button presses.
 
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daveangel
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Joined: October 20th, 2003, 4:05 pm

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November 12th, 2010, 1:33 pm

my bank stops you after 3 attempts
knowledge comes, wisdom lingers
 
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Traden4Alpha
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Joined: September 20th, 2002, 8:30 pm

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November 12th, 2010, 1:40 pm

QuoteOriginally posted by: daveangelmy bank stops you after 3 attemptsWhen have we ever let reality ruin a perfectly good brainteaser?
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