import sys

F = [1, 1]
n = 1
limit = 10 ** 15
i = 2
while True:
    x = F[i - 1] + F[i - 2]
    if x > limit:
        break
    F.append(x)
    i += 1

input = sys.stdin.readlines()
A = [int(s) for s in input]
A.reverse()
k = len(A)
ans = 0
for i in range(k):
    t = 0
    tt = 0
    if A[i] in F:
        if A[i] == 1:
            xx = i
            yy = F.index(A[i]) + 1
            while xx < k and yy < len(F) and A[xx] == F[yy]:
                tt += 1
                xx += 1
                yy += 1

        xx = i
        yy = F.index(A[i])
        t = 0
        while xx < k and yy < len(F) and A[xx] == F[yy]:
            t += 1
            xx += 1
            yy += 1

        ans = max(ans, t, tt)


print(ans)