发布时间：2015-04-02 19:08:54

import java.util.HashMap;import java.util.Map;import java.util.Stack;//Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.////The brackets must close in the correct order, "()" and "()[]{}" are all valid but "(]" and "([)]" a.........【阅读全文】

发布时间：2015-04-02 15:38:55

/Remove Nth Node From End of List Total Accepted: 46481 Total Submissions: 167543 My Submissions Question Solution //Given a linked list, remove the nth node from the end of list and return its head.////For example,////   Given linked list: 1->2->3->4->5, and n = 2.////   After.........【阅读全文】

发布时间：2015-04-02 15:23:09

mport java.util.ArrayList;import java.util.Arrays;import java.util.List;//Given an array S of n integers, are there elements a, b, c, and d in S such that a + b + c + d = target? Find all unique quadruplets in the array which gives the sum of target.////Note://Elements in a quadruplet (a,.........【阅读全文】

发布时间：2015-04-01 16:50:16

//Given a digit string, return all possible letter combinations that the number could represent.////A mapping of digit to letters (just like on the telephone buttons) is given below.////////Input:Digit string "23"//Output: ["ad", "ae", "af", "bd", "be", "bf", "cd", "ce", "cf"].import java..........【阅读全文】

发布时间：2015-04-01 15:58:33

//3Sum Closest Total Accepted: 33841 Total Submissions: 125526 My Submissions Question Solution //Given an array S of n integers, find three integers in S such that the sum is closest to a given number, target. Return the sum of the three integers. You may assume that each input would have exa.........【阅读全文】