231_power_of_two.py

# Solution 1

class Solution:
    def isPowerOfTwo(self, n: int) -> bool:
        tmp = 1
        ans = False
        while tmp <= n:
            if tmp == n:
                ans = True
                break
            tmp += tmp
        return ans


# Solution 2

class Solution:
    def isPowerOfTwo(self, n: int) -> bool:
        return (n > 0) and (n & (n-1) == 0)

'''
    This is my personal record of solving Leetcode Problems. 
    If you have any questions, please discuss them in [Issues](https://github.com/mengxinayan/leetcode/issues).
    Copyright (C) 2020-2022  mengxinayan

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
'''