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shaan_iitk

Say I have a three digit combination lock. What is the minimum number of trials I need on the combination to ensure that I get the correct combination? Hint.. answer is not 10^3 ...

  • 2 years ago
  • 2 years ago

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  1. KingGeorge
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    If I type in these numbers; 0123456789, will it count as trying all of 012, 123, 234, 345, 456, 567, 678, and 789?

    • 2 years ago
  2. KingGeorge
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    Or only 012, 345, 678, 9?

    • 2 years ago
  3. shaan_iitk
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    012, 345, 678

    • 2 years ago
  4. KingGeorge
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    Are there any other restrictions? Otherwise, I don't see how it could be anything but \(10^3\).

    • 2 years ago
  5. campbell_st
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    well there are 10^3 possible combinations... so you could take 10^3 -1 attempts before you get the successful combination

    • 2 years ago
  6. campbell_st
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    that is assuming the correct combination is the last 1 entered

    • 2 years ago
  7. campbell_st
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    then its 9^3 - 1 since only 9 digits

    • 2 years ago
  8. campbell_st
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    so 728 trials may be needed

    • 2 years ago
  9. campbell_st
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    minimum is 1 trial as you get it 1st go

    • 2 years ago
  10. shaan_iitk
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    Okk .. I would elaborate the question ... I have a three digit combination lock with each digit having 10 possibilities. Once the correct combination is entered the lock opens automatically. How will I optimize my search so as to ensure that I get the combination in the mimimum number of trials. Whst is the minimum number of trials? None of the answers given so far are correct

    • 2 years ago
  11. campbell_st
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    well you gave us 9 digits 0 to 8

    • 2 years ago
  12. Ishaan94
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    Is this really possible? I mean is there a algorithm for this system which could be faster than the brute force algorithm.

    • 2 years ago
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