package main

import . "fmt"

func main() {
	var aw,ab,bw,bb,c,d int
	Scan(&aw,&ab,&bw,&bb,&c,&d)
	if c>ab {
		aw -= c-ab
		bw += c-ab
	}
	if d>bw {
		aw += bw
	} else {
		aw += d
	}
	Println(aw)
}