import sys

sys.setrecursionlimit(10 ** 6)
int1 = lambda x: int(x) - 1
p2D = lambda x: print(*x, sep="\n")
def MI(): return map(int, sys.stdin.readline().split())
def MI1(): return map(int1, sys.stdin.readline().split())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]

def main():
    aa=[int(input()) for _ in range(5)]
    ans=0
    if aa[3:]==[1,1]:
        ans=1
        aa.pop()
    fibo=[1,1]
    while fibo[-1]<aa[-1]:
        fibo.append(fibo[-1]+fibo[-2])
    while aa:
        a=aa.pop()
        if a==fibo[-1]:
            ans+=1
            fibo.append(fibo[-1] + fibo[-2])
        else:
            break
    print(ans)

main()