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算法题，拼接出最大值

Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the array, and it should return false if every element

Given an array of size n, find the majority element. The majority element is the element that appears more than ⌊ n/2 ⌋ times.You may assume that the array is non-empty and the majority element

存在一个数组，数组大小为2n+1，里面有n对个数，加上另外一个单独出现的数，例如：1,2,2,3,1.(数组是无序的，考虑排序的话一定会超过限制)这5个数中的单独的数就是3，要你用你能想到的最高效率的方法找出来。=====================================int testData[]={1,2,2,3,1};int data=0; for(in

第13题：整数转换成罗马数字&第14题：罗马数字转换成整数写在前面：这两道题合起来写吧，其实整数转罗马数字我前天就写完了，当我想写罗马数转整数的时候竟然脑子一片空白，想了几分钟就想起来Map，本着学习的目的最终还是不想用Map，坚持C语言，今天脑子里直接涌出了Switch方式转换，看来“蹲在马桶上编程”的方式还是蛮不错的o(^▽^)o整数转罗马数字：主要建立对应

//表示对递归掌握的不是很熟，链表的操作好多都是递归实现！！！是时候好好学学递归了 Remove Duplicates from Sorted List   Given a sorted linked list, delete all duplicates such that each element appear only once.For example

You are climbing a stair case. It takes n steps to reach to the top.Each time you can either climb 1 or 2 steps. In how many distinct ways can you climb to the top?Subscribe to see which c

题目：Given a non-negative number represented as an array of digits, plus one to the number.          The digits are stored such that the most significant digit is at the head of the list.含义：尼玛！！

Given a sorted array, remove the duplicates in place such that each element appear only once and return the new length.Do not allocate extra space for another array, you must do this in place with

Given an integer n, return the number of trailing zeroes in n!.Note: Your solution should be in logarithmic time complexity.//求阶乘后面0的个数，可以通过判断此数是零的多好倍数public class Solution {       pub

Given a string s consists of upper/lower-case alphabets and empty space characters ' ', return the length of last word in the string.If the last word does not exist, return 0.Note: A word is

char a='2';char b='A';System.out.println(Integer.parseInt(a+""));System.out.println(Character.valueOf(b)+0);System.out.println(b+0);

Related to question Excel Sheet Column TitleGiven a column title as appear in an Excel sheet, return its corresponding column number.For example: A -> 1 B -> 2 C -> 3 ...

Assume you are an awesome parent and want to give your children some cookies. But, you should give each child at most one cookie. Each child i has a greed factor gi, which is the minimum size of a c

You are given a map in form of a two-dimensional integer grid where 1 represents land and 0 represents water. Grid cells are connected horizontally/vertically (not diagonally). The grid is completely

/** * 对int数组进行升序排序 * * @param sort[]：待排序的数组 * @param asc_type：值为true，表示升序排序；传入值为false，表示降序排序 * @return 返回排序后的int数组 */ public int[] bubble_sort(int sort[],boole...

short s1 =1; s1 = s1 + 1;有什么错? short s1 = 1; s1 += 1;有什么错？short s1=1; s1=(short)(s1+1); s1+=1;short s1 = 1; s1 = s1 + 1; （s1+1运算结果是int型，需要强制转换类型） short s1 = 1; s1 += 1;（可以正确编译）

1.单例模式（有的书上说叫单态模式其实都一样）该模式主要目的是使内存中保持1个对象。看下面的例子：package org.sp.singleton;//方法一public class Singleton {//将自身的实例对象设置为一个属性,并加上Static和final修饰符private static final Singleton instance = n

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

You are playing the following Nim Game with your friend: There is a heap of stones on the table, each time one of you take turns to remove 1 to 3 stones. The one who removes the last stone will be the

Write a function to delete a node (except the tail) in a singly linked list, given only access to that node.Supposed the linked list is 1 -> 2 -> 3 -> 4 and you are given the third node with value

Given two strings s and t, write a function to determine if t is an anagram of s.For example,s = "anagram", t = "nagaram", return true.s = "rat", t = "car", return false.Note:You may a

Given two binary trees, write a function to check if they are equal or not.Two binary trees are considered equal if they are structurally identical and the nodes have the same value.Subscr

Given a linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?表示对递归真的是比较不会用啊，大神们如果有好的学习递归的信息，留下脚印啊！循环实现表示超时！！！/** * Definition for sin

//丑数就TM丑所谓一个数m是另一个数n的因子，是指n能被m整除，也就是n % m == 0。根据丑数的定义，丑数只能被2、3和5整除。也就是说如果一个数如果它能被2整除，我们把它连续除以2；如果能被3整除，就连续除以3；如果能被5整除，就除以连续5。如果最后我们得到的是1，那么这个数就是丑数，否则不是。 Write a program to check whether

Write an algorithm to determine if a number is "happy".A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares o...

Given a non-negative integer num, repeatedly add all its digits until the result has only one digit.For example:Given num = 38, the process is like: 3 + 8 = 11, 1 + 1 = 2. Since 2 has on

Given an integer, write a function to determine if it is a power of two.Credits:Special thanks to @jianchao.li.fighter for adding this problem and creating all test cases.===============

override（重写） 1）方法名、参数、返回值相同。2）子类方法不能缩小父类方法的访问权限。3）子类方法不能抛出比父类方法更多的异常(但子类方法可以不抛出异常)。4）存在于父类和子类之间。5）方法被定义为final不能被重写。overload（重载）1）参数类型、个数、顺序至少有一个不相同。  2）不能重载只有返回值不同的方法名。3）存在于父类和子类、同类中

Interface只能有成员常量，只能是方法的声明；而abstract class可以有成员变量，可以声明普通方法和抽象方法。声明方法的存在而不去实现它的类被叫做抽象类（abstract class），它用于要创建一个体现某些基本行为的类，并为该类声明方法，但不能在该类中实现该类的情况。不能创建abstract 类的实例。然而可以创建一个变量，其类型是一个抽象类，并让它指向具体子类的一个实

Java 提供两种不同的类型：引用类型和原始类型（或内置类型）。Int是java的原始数据类型，Integer是java为int提供的封装类。Java为每个原始类型提供了封装类。原始类型封装类booleanBoolean  charCharacter  byteByte  shortShort  intInteger  longLong  floatFloat  doubleDou

访问 Public Protected 缺省的 Private同类 √ √√ √同包 √ √√ ×子类 √ √× ×通用性 √ ×× ×

1）抽象：抽象就是忽略一个主题中与当前目标无关的那些方面，以便更充分地注意与当前目标有关的方面。抽象并不打算了解全部问题，而只是选择其中的一部分，暂时不用部分细节。抽象包括两个方面，一是过程抽象，二是数据抽象。2）继承：继承是一种联结类的层次模型，并且允许和鼓励类的重用，它提供了一种明确表述共性的方法。对象的一个新类可以从现有的类中派生，这个过程称为类继承。新类继承了原始类的特性，

ArrayList和Vector都是使用数组方式存储数据，此数组元素数大于实际存储的数据以便增加和插入元素，它们都允许直接按序号索引元素，但是插入元素要涉及数组元素移动等内存操作，所以索引数据快而插入数据慢，Vector由于使用了synchronized方法（线程安全），通常性能上较ArrayList差。HashMap是Hashtable的轻量级实现（非线程安全的实现），他们都完成了Map接口

Given a binary tree, find its maximum depth.The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.Subscribe to see which compani

Given a string, find the first non-repeating character in it and return it's index. If it doesn't exist, return -1.Examples:s = "leetcode"return 0.s = "loveleetcode",return 2.Note:

Given two strings s and t which consist of only lowercase letters.String t is generated by random shuffling string s and then add one more letter at a random position.Find the letter that was

Merge two sorted linked lists and return it as a new list. The new list should be made by splicing together the nodes of the first two lists.public class Solution { public ListNode mergeTwoLis

Given a linked list, swap every two adjacent nodes and return its head.For example,Given 1->2->3->4, you should return the list as 2->1->4->3.Your algorithm should use only constant space. Y

Say you have an array for which the ith element is the price of a given stock on day i.If you were only permitted to complete at most one transaction (ie, buy one and sell one share of the stock),