n=int(input().strip())
numerators=[1]
denominators=[2]
i=2
while i<=n:
    numerators.append(denominators[-1])
    denominators.append(denominators[-1]*2+numerators[-2])
    i+=1
for i in range(n):
    n=denominators[i]+numerators[i]
    d=denominators[i]
    if len(str(n))>len(str(d)):
        print(i+1)