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Thread: Pin code generator with recursion

  1. #1
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    Default Pin code generator with recursion

    Hello, please help me with my home work...

    Create program which generates pin codes (allowed numbers 1-9), the user inputs length of the code and the biggest number
    This has to be done with recursion

    So the program would be:

    Length: 3
    biggest number: 2

    111
    112
    121
    122
    211
    212
    221
    222

    Length: 5
    biggest number: 4

    11111
    11112
    11113
    11114
    11121
    ...
    44444

  2. #2
    Super Moderator Norm's Avatar
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    Default Re: Pin code generator with recursion

    What have you tried?

    Be sure to wrap your posted code with code tags:

    [code]
    **YOUR CODE GOES HERE**
    [/code]

    to get highlighting and preserve formatting.
    If you don't understand my answer, don't ignore it, ask a question.

  3. #3
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    Default Re: Pin code generator with recursion

    Hello Norm,

    my first approach was to create an array[length] and fill it with 1, then call a method which adds recursively every index up until the highest number, that would've been too easy...
    then I got maybe the craziest idea ever, to look for the patterns and try to create a mathematical approach to it... way too complicated...
    then I tried to create a method which calculates combinations, store them in an array and then sort the array. But that didn't work either.
    Last edited by Mironoff; August 18th, 2019 at 05:10 AM.

  4. #4
    Super Moderator Norm's Avatar
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    Default Re: Pin code generator with recursion

    The desired output looks like a series of incremented numbers in a different base and first digit. Instead of base 10 and with starting digit of 0 the base is the "biggest number" + 1 and the starting digit is 1.
    So starting with 111 base 2+1 you get the first series you posted by adding 1 to the number until the max of 222 is reached.
    If you don't understand my answer, don't ignore it, ask a question.

  5. The Following User Says Thank You to Norm For This Useful Post:

    Mironoff (August 19th, 2019)

  6. #5
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    Default Re: Pin code generator with recursion

    Thanks a million Norm! I was blind I try that right away.
    Last edited by Mironoff; August 19th, 2019 at 03:31 AM.

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