JackZhangNJU的专栏

Given an array of integers, every element appears twice except for one. Find that single one.Note: Your algorithm should have a linear runtime complexity. Could you implement it without using extra me

All DNA is composed of a series of nucleotides abbreviated as A, C, G, and T, for example: “ACGAATTCCG”. When studying DNA, it is sometimes useful to identify repeated sequences within the DNA.Write

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, the 32-bit integer ’11’ has binary representation 0000000000

Given a range [m, n] where 0 For example, given the range [5, 7], you should return 4.这道题最自觉的做法就是循环做位and操作，但是我在网上看到了一个做法， 想法很棒，这道题可以直接转化为另一个问题：再一串连续的数组中，寻找他们的公共前缀。直接暴力去计算可能要超时代码如下：/* * 这道题

A frog is crossing a river. The river is divided into x units and at each unit there may or may not exist a stone. The frog can jump on a stone, but it must not jump into the water.Given a list of s...

Given a non-empty array of numbers, a0, a1, a2, … , an-1, where 0 ≤ ai < 231.Find the maximum result of ai XOR aj, where 0 ≤ i, j < n.Could you do this in O(n) runtime?Example:Input: [3,...

Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters.This is case sensitive, for example “Aa” is not consi...

Given a positive integer, check whether it has alternating bits: namely, if two adjacent bits will always have different values.Example 1: Input: 5 Output: True Explanation: The binary represent...

The Hamming distance between two integers is the number of positions at which the corresponding bits are different.Given two integers x and y, calculate the Hamming distance.Note: 0 ≤ x, y < 2...

The Hamming distance between two integers is the number of positions at which the corresponding bits are different.Now your job is to find the total Hamming distance between all pairs of the given n...

A character in UTF8 can be from 1 to 4 bytes long, subjected to the following rules:For 1-byte character, the first bit is a 0, followed by its unicode code. For n-bytes character, the first n-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 and return them as an array.Example: For num = 5 you

Given an array of integers, every element appears three times except for one, which appears exactly once. Find that single one.Note: Your algorithm should have a linear runtime complexity. Could you i

Reverse bits of a given 32 bits unsigned integer.For example, given input 43261596 (represented in binary as 00000010100101000001111010011100), return 964176192 (represented in binary as 00111001011110

Given a complete binary tree, count the number of nodes.Definition of a complete binary tree from Wikipedia: In a complete binary tree every level, except possibly the last, is completely filled, a

Given an integer, write a function to determine if it is a power of two.就是判断一个数是不是2的次方数。代码如下：public class Solution{ public boolean isPowerOfTwo(int n) { if(n0) re

Given an array of numbers nums, in which exactly two elements appear only once and all the other elements appear exactly twice. Find the two elements that appear only once.For example:Given nums =

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 nums = [0, 1, 3] return 2.Note: Your algorithm should run in

Given an integer, write a function to determine if it is a power of three.Follow up: Could you do it without using any loop / recursion?最直接的方法是使用log函数，还有一个从网上看到的别的方法，也可以，不过很难想。建议和这一道题leetcode 3

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 number of bits in the code, print the sequence of gr

Given a sorted array consisting of only integers where every element appears twice except for one element which appears once. Find this single element that appears only once.Example 1: Input: [1,1,...