from collections import deque
N = int(input())
if N==1:
    print(1)
else:
    flag = -1
    for k in range(2,100+1):
        A = [0]*k
        A[0] = 1
        A = deque(A)
        for i in range(1,200+1):
            a = sum(A)
            if a==N:
                flag = k
                break
            elif a>N:break
            A.pop()
            A.appendleft(a)
        if flag>0:break
    print(flag)