#!/usr/bin/env pypy3


def min_num_ops(n):
    assert 1 <= n
    res = 0
    while n > 1:
        res += 1
        d, m = divmod(n, 2)
        if m == 0:
            n = d
        else:
            n += 1
    return res


def main():
    print(min_num_ops(int(input())))


if __name__ == '__main__':
    main()