from bisect import bisect_right

DP = [0 for _ in range(75)]
DP[0] = DP[1] = 1
for i in range(2, 75):
    DP[i] = DP[i - 1] + DP[i - 2]

A = [int(input()) for _ in range(5)]
if A[4] == 1 and A[3] == 1:
    if A[2] != 2:
        print(2)
    elif A[1] != 3:
        print(3)
    elif A[0] != 5:
        print(4)
    else:
        print(5)
    exit()
ans = 0
pre_idx = -1
for i in range(4, -1, -1):
    idx = bisect_right(DP, A[i]) - 1
    if DP[idx] != A[i]:
        break
    if pre_idx != -1 and idx != pre_idx + 1:
        break
    ans += 1
    pre_idx = idx
print(ans)