import sys
def solve():
    a = [int(sys.stdin.readline()) for _ in range(5)]
    f = [1, 1]
    while f[-1] + f[-2] <= 10 ** 15:
        f.append(f[-1] + f[-2])
    s = set(f)
    ok_pair = set()
    for i in range(len(f) - 1):
        ok_pair.add((f[i], f[i + 1]))
    for n in range(5, 0, -1):
        ok = 1
        if n == 1:
            if a[4] not in s:
                ok = 0
        else:
            for i in range(n - 1):
                x = a[4 - i]
                y = a[4 - i - 1]
                if (x, y) not in ok_pair:
                    ok = 0
                    break
        if ok:
            print(n)
            return
    print(0)

if __name__ == '__main__':
    solve()