Problem 2

Problem

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, ...

By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.

Code

#include <iostream>
using namespace std;

static long result = 2;
void fibonacciSequence(long first, long second)
{
    long sum = first + second;
    if (sum >= 4000000)
    {
        return;
    }
    if (sum%2 == 0)
    {
        result += sum;
    }
    cout << endl;
    fibonacciSequence(second, sum);
}

int main()
{
    fibonacciSequence(1,2);
    cout << result << endl;
}