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 memory? 题目标签:Hash Table 题目给了我们一个 nums array, array 里…
-------------------------------- 这道题好坑啊,自己说是2*n+1个数字,结果有组测试数据竟然传了个空数组进来... 经典位算法: n^n==0 n^0==n AC代码: public class Solution { /** *@param A : an integer array *return : a integer */ public int singleNumber(int[] A) { if(A.length==0) return 0; int n=A…
题目描述: 我的代码: public class Solution { /* * @param num: a positive number * @return: true if it's a palindrome or false */ public boolean isPalindrome(int num) { // write your code here int i=0,count=0; int n = num; while(n != 0) { n/=10; count++; } int…
Given an array of integers, find two numbers such that they add up to a specific target number. The function twoSum should return indices of the two numbers such that they add up to the target, where index1 must be less than index2. Please note that…
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 of its digits, and repeat the process until the number…
Write a program to check whether a given number is an ugly number`. Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while 14 is not ugly since it includes another prime factor 7. Notice Note that…
class Solution { public: /** * @param nums: a vector of integers * @return: an integer */ int findMissing(vector<int> &nums) { // write your code here int n = nums.size(); ; ; i <= n; i++) number ^= i; ; i < n; i++) number ^= nums[i]; retu…
面试题3 -- 搜索二维矩阵 写出一个高效的算法来搜索 m × n矩阵中的值. 这个矩阵具有以下特性: 1. 每行中的整数从左到右是排序的. 2. 每行的第一个数大于上一行的最后一个整数. public class Solution { /** * @param matrix, a list of lists of integers * @param target, an integer * @return a boolean, indicate whether matrix contains…
136. Single Number Given an array of integers, every element appears twice except for one. Find that single one. (Easy) Note:Your algorithm should have a linear runtime complexity. Could you implement it without using extra memory? 分析: 第一问属于技巧题,做过就会,…
