classSolution{publicbooleanisPowerOfTwo(intx){returnx >0&& (x ==1|| (x %2==0&& isPowerOfTwo(x /2))); } } Python 实现(递归) classSolution:defisPowerOfTwo(self, x):""" :type n: int :rtype: bool """returnx >0and(x ==1or(x %2==0andself.isPowerOfTwo(x //2))) 复...
【LeetCode】Power of Two 问题描写叙述 Given an integer, write a function to determine if it is a power of two. 意:推断一个数是否是2的n次幂 算法思想 假设一个数小于或等于0。一定不是2的幂次数 假设一个大于0且数是2的n次幂,则其的二进制形式有且仅有一个1,反之成立。 算法实现 publicclassS...
leetcode Power of Two题解 题目描述: Given an integer, write a function to determine if it is a power of two. Example 1: Example 2: Example 3: 中文理解:给定一个数,判断这个数是不是2的幂次方。 解题思路:从0开始遍历到n,若pow(2,i)==n返回true,否则返回false。 代码(java): ......
leetcode.com/problems/power-of-three/ 2.1)采用循环 class Solution: def isPowerOfThree(self, n: int) -> bool: if not n: return False while n: if n==1: return True if n%3: return False n //=3 return True Runtime: 80 ms, faster than 52.08% of Python3 online submissionsMemo...
class Solution: def reorderedPowerOf2(self, n: int) -> bool: # 先计算 n 的十进制位出现次数,方便后续复用 digit_to_cnt: Counter = Counter(str(n)) # 枚举所有 2 的幂次方 for i in range(31): # 如果所有十进制数位的出现次数都相同,则 n 和 1 << i 是按十进制位重排的, #则 n 满足...
从表格中可以看出,如果整数 xx 是2 的幂的话,整数 xx 与x−1x−1 的二进制表示进行与运算,结果为 0,因此我们就可以写出解法1 的第二种实现方式。Java 实现class Solution { public boolean isPowerOfTwo(int x) { return x > 0 && ((x & (x - 1)) == 0); } } 1 2 3 4 5Python...
Power of Two Given an integer, write a function to determine if it is a power of two. 整除法 复杂度 时间O(1) 空间 O(1) 思路 最简单的解法,不断将原数除以2,一旦无法整除,余数不为0,则说明不是2的幂,如果整除到1,说明是2的幂。
power of two power-of-two classSolution{public:boolisPowerOfTwo(intn){returnn>=1&&!(n&(n-1));}}; 1. 2. 3. 4. 5. 6. n=10000***000, <=> n&(n-1)=0 是这种方法的核心 https://leetcode.com/discuss/40202/only-push-others-using-queue-combination-shared-solutions...
LeetCode笔记:342. Power of Four Given an integer (signed 32 bits), write a function to check whether it is a power of 4. Example: Given num = 16, return true. Given num = 5, return false. Follow up: Could you solve it without loops/recursion?
Power of Two Given an integer, write a function to determine if it is a power of two. Credits: Special thanks to @.fighter for adding this problem and creating all test cases. AI检测代码解析 class Solution { public: ...