a = list(map(int, input().split()))
def check(x):
  y = x + x
  res = 0
  for i in range(5):
    res += a[i] * x[i]
    s = sum(y[i:i+3])
    if s == 0:
      return (False, 0)
  return (True, res)

ans = None
for i in range(1, 2**5):
  x = [(i>>j)&1 for j in range(5)]
  y = check(x)
  if y[0]:
    if ans == None or ans > y[1]:
      ans = y[1]

print(ans)