#include <algorithm>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <functional>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <utility>
#include <valarray>
#include <vector>

#define N 1000
#define re(i,n) for(int i=0;i<(n);i++)
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define fe(i,n,f) for_each(i,n,f)
#define bw(a,b,c) (((a)<=(b))&&((b)<=(c)))
using namespace std;

typedef long long ll;
typedef unsigned long long ull;

int main(void){
	int a,b,c,d,e,f;
	cin>>a>>b>>c>>d>>e>>f;
	int s,t;
	s=max(e-b,0); //pw
	t=min(b,e);  //pb
	a-=s;
	b-=t;
	c+=s;
	d+=t;
	t=max(f-c,0);
	s=min(c,f);
	c-=s;
	d-=t;
	a+=s;
	b+=t;

	cout<<a<<endl;
	return 0;
}