import math

def main():
    N = int(input())

    if N == 1:
        print(0)
        return
    n = math.log2(N)
    if not n % 1:
        print(int(n))
    else:
        i = int(n + 1)
        up = 2 ** i - N + i + 1
        mid = N + 1 // 2
        i = int(n)
        if N & 1:
            down = 2 ** i - mid + 2 + i + 1
        else:
            down = 2 ** i - mid + 1 + i + 1
        print(min(up, down))

main()