def fnc(s):
    t = list(map(str,range(1,s+1)))
    pos = 0
    count = 1
    li = []
    while t[pos] != t[-1]:
        b = bin(int(t[pos]))
        tmp = str(b).count("1")
        if pos + tmp > len(t)-1:
            pos -= tmp
        else :
            pos += tmp
        if t[pos] in li:
            return -1
        count += 1
        li.append(t[pos])
    return count
print(fnc(int(input())))