Jumlah Fibonaci Genap

#include <cstdlib>
#include <stdio.h>
#include <iostream>

using namespace std;

int main(int argc, char** argv) {
    int a=1, b=0, c, jumlah;
    while(c<3000000) {
        if(c % 2 == 0) {
            jumlah += c;
        }
        c = a+b;
        b = a;
        a = c;
    }
    cout << jumlah;
    cout << endl;
    return 0;
}