Project Euler #2: Even Fibonacci numbers

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.

Solution in C++

#include 

int main()
{
	int i, y, z, x = 1;
	unsigned long long total;
	std::cout << "Enter fibbonacci seed number: "; std::cin >> i;
	std::cout << std::endl << "Enter the maximum number: "; std::cin >> z;

	while(i <= z){
		y = i;
		i += x;
		if(i & 0x1){
			total += i;
		}
		x = y;
	}
	std::cout << total;
}