프로젝트 오일러 문제 2

Even Fibonacci numbers

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, ...

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

400만까지의 범위에서 짝수인 피보나치 수의 합을 구하기

int Problem002(int first, int second, int scope)
{
	int ret = 0;
	int third = first + second;

	if (first % 2 == 0)
	{
		ret += first;
	}
	if (second % 2 == 0)
	{
		ret += second;
	}

	while (true)
	{
		if (third > scope)
		{
			break;
		}
		if (third % 2 == 0)
		{
			ret += third;
		}
		first = second;
		second = third;
		third = first + second;
	}
	return ret;
}