# -*- coding: utf-8 -*-
"""
No.149 碁石の移動
https://yukicoder.me/problems/no/149

"""
import sys
from sys import stdin
input = stdin.readline


def main(args):
    Aw, Ab = map(int, input().split())
    Bw, Bb = map(int, input().split())
    C, D = map(int, input().split())

    # C個の移動
    if C <= Ab:
        Bb += C
        Ab -= C
    else:
        Bb += Ab
        Aw -= (C - Ab)
        Bw += (C - Ab)
        Ab = 0

    # D個の移動
    if D <= Bw:
        Aw += D
        Bw -= D
    else:
        Aw += Bw

    print(Aw)


if __name__ == '__main__':
    main(sys.argv[1:])