From: Panagiotis Atmatzidis <atma@...>
Date: 2009-12-19T04:50:37+09:00
Subject: Question about sum of fibonacci sequene [PROJECT EULER]

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Dear Sirs,

Just to improve my programming skills and experience I found amusing solving problems like the ones posed by project Euler. Doing so, using Ruby is a joy, compared to Objective-C that I've used for the same purpose in the past.

I'm stuck in the second problem though. Here is the issue:

Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:

1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...

Find the sum of all the even-valued terms in the sequence which do not exceed four million.

I think that my code solves it. Works when I test it to smaller fractions, can someone reply if there's something wrong with this snippet:
- ---------------
# fibonacci

a = 1
b = 0
sum = 0
while a <= 4000000
 # get the old value of "a"
 c = a + b
 #puts c
 if (c % 2 != 0)
  sum = sum + c
 end
 b = a
 a = c
end
  
puts sum
- ---------------

Well my result is: 10316618 . I know that the original Fibonacci sequence will have a (+1) in the beginning of the loop, but (probably) for the sake of convenience is ignored. The system however returns a "false error" in both 10316618 and 10316618 + 1.

Thanks in advanced & best regards 



Panagiotis (atmosx) Atmatzidis

email:	atma@convalesco.org
URL:	http://www.convalesco.org
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- --
The wise man said: "Never argue with an idiot. They bring you down to their level and beat you with experience."

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