Problem 2 is below:

Problem 2: "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." (Project Euler Problem #2)

Tests:

module Problem2Tests open NUnit.Framework [<TestFixture>] type Problem2__When_finding_sum_of_even_valued_terms_in_the_fibonacci_sequence_up_to_89 () = [<Test>] member this.should_return_sum_of_44 () = let result = Problem2.FindSum 89 Assert.AreEqual(44, result) [<TestFixture>] type Problem2__When_finding_sum_of_even_valued_terms_in_the_fibonacci_sequence_below_4_million () = [<Test>] member this.should_return_sum_of_4613732 () = let result = Problem2.FindSum 4000000 Assert.AreEqual(4613732, result)Code:

module Problem2 let FindSum max = let rec getFibonacciSumForEvens lastValue currentValue accumulator = match lastValue + currentValue with | sum when sum >= max -> accumulator | sum when sum % 2 = 0 -> getFibonacciSumForEvens currentValue sum (accumulator + sum) | sum -> getFibonacciSumForEvens currentValue sum accumulator getFibonacciSumForEvens 0 1 0

## No comments:

## Post a Comment