#include <algorithm>
#include <iostream>

using namespace std;

int main(int argc, const char* argv[])
{
	int Aw, Ab;
	int Bw, Bb;
	int C, D;
	cin >> Aw >> Ab >> Bw >> Bb >> C >> D;
	int idealAw = min(Aw, Aw + Ab - C);
	idealAw		= idealAw + min(Bw + (Aw - idealAw), D);
	cout << idealAw << endl;
	return 0;
}