A = 5.times.map { gets.to_i }

def fib(x)
  res = [1, 1]

  (x - 2).times do
    res << res[-2] + res[-1]
  end

  res
end

nums = fib(100)
ans = 0

a = A[4]
idx = nums.index(a)

if idx
  cnt = 1

  (3).downto(0) do |j|
    idx += 1
    break if nums[idx] != A[j]
    cnt += 1
  end

  ans = cnt
end

a = A[4]
idx = nums.rindex(a)

if idx
  cnt = 1

  (3).downto(0) do |j|
    idx += 1
    break if nums[idx] != A[j]
    cnt += 1
  end

  ans = cnt if ans < cnt
end


puts ans