def Fib(n):
    a, b = 0, 1
    if n == 1:
        return a
    elif n == 2:
        return b
    else:
        for _ in range(n-2):
            a, b = b, a + b
        return b
fib = [Fib(n) for n in range(1, 100)]
del fib[0]
arr = [int(input()) for _ in range(5)][::-1]
ans_1 = 0
check = [1,2,3,5,8]
for i in range(5):
    if arr[i] == check[i]:
        ans_1 += 1
    else:
        break
ans = 0
if arr[0] in fib:
    ans += 1
    for i in range(1,5):
        if arr[i] == fib[fib.index(arr[0])+i]:
            ans += 1
        else:
            break
print(max(ans,ans_1))