A = list(map(int, input().split()))
B = list(map(int, input().split()))
CD = list(map(int, input().split()))

Aw = A[0]
Ab = A[1]
Bw = B[0]
Bb = B[1]

if CD[0] <= Ab:
    Ab -= CD[0]
    Bb += CD[0]
elif CD[0] > Ab:
    Aw -= (CD[0] - Ab)
    Bw += (CD[0] - Ab)
    if not Ab == 0:
        Bb += (CD[0] - Ab)
    Ab = 0

if CD[1] <= Bw:
    Aw += CD[1]
    Bw -= CD[1]
elif CD[1] > Bw:
    Aw += Bw
    Bb -= (CD[1] - Bw)
    if not Bw == 0:
        Ab += (CD[1] - Bw)
    Bw = 0

print(Aw)