
#include <iostream>
#include <fstream>
using namespace std;
int main()
{
ofstream myfile;
myfile.open("fib.txt");
int n, second_term = 0, previous_term = 1 , term_now, ;
long long sum_actual = 0, sum = 0;
for (n = 0; n<4000001; n++)
{
sum = previous_term + second_term ;
previous_term = second_term;
second_term = sum;
if(sum % 2 == 0) { sum_actual += sum; }
}
myfile << sum_actual;
myfile.close();
cout<<sum_actual;
cin.get();
return 0;
}