AW,AB=map(int,input().split())
BW,BB=map(int,input().split())
C,D=map(int,input().split())

boxA=AW+AB
boxB=BW+BB

if C<=AB:
    if D>=BW:
        print(AW+BW)
    else:
        print(AW+D)
else:
    BW+=(C-AB)
    AW-=(C-AB)
    if D>=BW:
        print(AW+BW)
    else:
        print(AW+D)