#include <bits/stdc++.h>
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,b) FOR(i,0,b)
#define BE(c) c.begin(),c.end()
#define PB push_back
#define F first
#define S second
#define BEB(s) s
using namespace std;
int main(){
	int aw,ab,bw,bb,c,d;
	cin>>aw>>ab>>bw>>bb>>c>>d;
	if(ab>=c){
		cout<<aw+min(bw,d)<<endl;
	}else{
		aw-=(c-ab);
		cout<<aw+min(bw+(c-ab),d)<<endl;
	}
	return 0;
}