zhangchaosd的博客

原题目链接 ：https://leetcode-cn.com/problems/powx-n/思路：因为 n 是指数，所以可以把 n 分解为多个 2 的 j次方相加，于是就可以扫描 n 的二进制，每遇到一个 1，就通过迭代平方快速算出当前因子并乘到 ans 上n<0 时注意 n 为 INT_MIN 的情况class Solution {public: ...

题目链接思路：用[1 - high] 的结果减去 [1 - low] 的结果；数位dp的方法，从最高位开始统计，注意处理 d 为 0 的情况。dp数组只是为了保存每次调用函数的结果，用来加快速度。时间复杂度和空间复杂度都是 O(n)，n 为输入数字的位数class Solution { vector<int>s; int n; in...

Given a string s, find the longest palindromic substring in s. You may assume that the maximum length of s is 1000.Example:Input: "babad"Output: "bab"Note: "aba" is also a valid answer. Example:I...

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility)P A H NA P L S I I G...

Given a 32-bit signed integer, reverse digits of an integer.Example 1:Input: 123Output: 321Example 2:Input: -123Output: -321Example 3:Input: 120Output: 21Note:Assume we are dealing with an envi...

Implement atoi to convert a string to an integer.Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases....

Given a string, find the length of the longest substring without repeating characters.Examples:Given "abcabcbb", the answer is "abc", which the length is 3.Given "bbbbb", the answer is "b", with the l...

There are two sorted arrays nums1 and nums2 of size m and n respectively.Find the median of the two sorted arrays. The overall run time complexity should be O(log (m+n)).Example 1:nums1 = [1, 3]nums2...