James Pan

原题网址：https://leetcode.com/problems/missing-number/Given an array containing n distinct numbers taken from 0, 1, 2, ..., n, find the one that is missing from the array.For example,Given n

原题网址：https://leetcode.com/problems/hamming-distance/The Hamming distance between two integers is the number of positions at which the corresponding bits are different.Given two integers x 

原题网址：https://leetcode.com/problems/gray-code/The gray code is a binary numeral system where two successive values differ in only one bit.Given a non-negative integer n representing the total

原题网址：https://leetcode.com/problems/add-binary/Given two binary strings, return their sum (also a binary string).For example,a = "11"b = "1"Return "100".方法一：使用字符串来表示。public class So

原题网址：https://leetcode.com/problems/n-queens-ii/Follow up for N-Queens problem.Now, instead outputting board configurations, return the total number of distinct solutions.方法一：深度优先搜索，使用一

原题网址：https://leetcode.com/problems/power-of-two/Given an integer, write a function to determine if it is a power of two.思路：数字n是2的整数次幂，当且仅当n的二进制表示有且只有一个1。public class Solution { public boo

原题网址：342. Power of Four 342. Power of Four 342. Power of Four 342. Power of FourGiven an integer (signed 32 bits), write a function to check whether it is a power of 4.Example:Given num =

原题网址：https://leetcode.com/problems/counting-bits/Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation

原题网址：https://leetcode.com/problems/maximum-product-of-word-lengths/Given a string array words, find the maximum value of length(word[i]) * length(word[j]) where the two words do not share comm

原题网址：https://leetcode.com/problems/range-sum-query-mutable/Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive.The update(i, val) function mo

原题网址：https://leetcode.com/problems/bitwise-and-of-numbers-range/Given a range [m, n] where 0 For example, given the range [5, 7], you should return 4.思路：总体思路就是求出m和n的高位比特的公共前缀。方法一：变动前缀本身。

原题网址：https://leetcode.com/problems/number-of-1-bits/Write a function that takes an unsigned integer and returns the number of ’1' bits it has (also known as the Hamming weight).For example

原题网址：https://leetcode.com/problems/reverse-bits/Reverse bits of a given 32 bits unsigned integer.For example, given input 43261596 (represented in binary as 00000010100101000001111010011100)

原题网址：https://leetcode.com/problems/single-number/Given an array of integers, every element appears twice except for one. Find that single one.Note:Your algorithm should have a linear runti

原题网址：https://leetcode.com/problems/single-number-ii/Given an array of integers, every element appears three times except for one. Find that single one.Note:Your algorithm should have a lin

原题网址：https://leetcode.com/problems/single-number-iii/Given an array of numbers nums, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the tw

原题网址：https://leetcode.com/problems/total-hamming-distance/The Hamming distance between two integers is the number of positions at which the corresponding bits are different.Now your job is