Note the difference between this counting system and the normal base-10 system

  • 21

    consider the letter 'A' to have a value of 1, 'B'->2 ..... 'Z'->26
    note that in the above notation, values are 1-based

    here our Radix (R) == 26

    the final value of a number X Y Z = X * R^2 + Y * R + Z

    this looks similar to base-10 decimal number but the biggest difference is that the numbers on every digit starts with 1, instead of 0., and the max on each digit goes up to R (Radix) instead of R-1

    for example
    Z== Radix
    then next number is AA = R + 1 = Z+1
    ZZ = R * R + R
    next number is AAA = 1*R^2 + 1 * R + 1 = ZZ +1

    so from the AAA notation to their sequence number (decimal) it's easy, but the other way is a bit tricky due to the way % and / operates

  • 0

    yeah, it is. I've spent quit a long time. But failed.

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