a_list = list(map(int,input().split()))
b_list = list(map(int,input().split()))
move_list = list(map(int,input().split()))
aw, ab = a_list
bw, bb = b_list
c, d = move_list

rw = 0
if c >= ab:
    rw = aw - (c - ab)
    bw += (c - ab)
else:
    rw = aw
    
if d >= bw:
    rw += bw
else:
    rw += d
    
print(rw)