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Fibonacci problem - Fortran Atom Feed 0

In Brief This program outputs the sum of all even numbers in the Fibonacci sequence that are smaller than 4 Million
# 's
 1! fibonacci.f95
2! Program to find the sum of all even Fibonacci numbers less than 4 million.
3
4
5program fibonacci
6
7implicit none
8! Define the variables.
9integer i,n(0:2000),sum
10
11print*, 'This program will find the sum of all even Fibonacci numbers'
12print*, 'that have values less than 4 million.'
13
14
15! Initialize the Fibonacci Sequence.
16n(0) = 1
17n(1) = 1
18! Initialize the Sum.
19sum=0
20! Supply the first two lines of output.
21print*, 'Number=', n(0), ' SUM=', sum
22print*, 'Number=', n(1), ' SUM=', sum
23
24do i=2,2000
25! Define the next number in the sequence.
26n(i) = n(i-1) + n(i-2)
27! Exit the loop if the latest number is greater than 4 million.
28if(n(i).ge.4e6) then
29exit
30end if
31! Only add the latest number if it is even.
32if(mod(n(i),2).eq.0) then
33sum=sum+n(i)
34end if
35! Print out the latest fibonacci number and the sum.
36print*, 'Number=', n(i), ' SUM=', sum
37
38end do
39
40print*, 'Fibonacci number now larger than 4 million'
41
42end program fibonacci

This program outputs the sum of all even numbers in the Fibonacci sequence that are smaller than 4 Million