Hi!
I'd just like to post my isHappy? method:
class Integer
def isHappy?
return to_s.split(//).collect{|digit| digit.to_i**2}.inject{|sum, n| sum +
n }.isHappy? while self!=1
true
rescue
false
end
end
puts
115485454654987986246476765451256546545241654555555555555555555555555555555555554125665146454122345444487.isHappy?
true
This method may return false negative (if happiness>maximum stack level),
though I doubt no one will ever find one!
Thanks for the quiz,
Eric
On Friday 01 September 2006 15:01, Ruby Quiz wrote:
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> -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
>=-=-=
>
> by Shane Emmons
>
> Write a program that tells whether a given integer is happy. A happy number
> is found using the following process: Take the sum of the squares of its
> digits, and continue iterating this process until it yields 1, or produces
> an infinite loop.
>
> For example the number 7:
>
> 7^2 = 49
> 4^2 + 9^2 = 97
> 9^2 + 7^2 = 130
> 1^2 + 3^2 + 0^2 = 10
> 1^2 + 0^2 = 1
>
> If a number is not happy than it is obviously unhappy. Now that you have
> this program, what is the largest happy number you can find? What is the
> happiest number between 1 and 1,000,000. I define the happiest number as
> the smallest number that finds the most other happy numbers with it, i.e. 7
> found four other numbers (49, 97, 130, and 10) making it a rank 4 in
> happiness.
>
> If you find all these examples trivial, write you program so that it will
> find happy numbers in other bases such as base 2 or 16. From there you can
> extend the program so that it finds happy bases (other than 2 and 4). A
> happy bases is a base where all numbers are happy. Good luck.