data = [+1, -2, +3, -4, +5, -6, +7, +8, -9, +10,
        -11, -12, +13, +14, -15, -16, +17, -18, +19, -20,
        +21, -22, -23, +24, -25, -26, -27, +28, -29, -30,
        +31, -32]

answer = 0

for i in data:
    if i > 0:
        answer += int(input()) + 4
    else:
        answer += -(int(input()) - 4)
print(answer)