摘要：
Given a roman numeral, convert it to an integer. Input is guaranteed to be within the range from 1 to 3999. Solution: Solution 2: Whenever the value o 阅读全文
摘要：
Write a function to find the longest common prefix string amongst an array of strings.Solution: 1 public class Solution { 2 public String longestC... 阅读全文
摘要：
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
摘要：
Given a string containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.The brackets must close in the c... 阅读全文
摘要：
Given an array and a value, remove all instances of that value in place and return the new length.The order of elements can be changed. It doesn't mat... 阅读全文
摘要：
Implement strStr().Returns the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack. Update (2014-11-02):The s... 阅读全文
摘要：
Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules.The Sudoku board could be partially filled, where empty cells are filled with... 阅读全文
摘要：
The count-and-say sequence is the sequence of integers beginning as follows:1, 11, 21, 1211, 111221, ...1 is read off as "one 1" or 11.11 is read off ... 阅读全文
摘要：
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 ... 阅读全文
摘要：
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.Solution:... 阅读全文
摘要：
Given two binary strings, return their sum (also a binary string). For example,a = "11"b = "1"Return "100".Solution: 1 public class Solution { 2 p... 阅读全文
摘要：
Given a non-negative number represented as an array of digits, plus N to the number.The digits are stored such that the most significant digit is at t... 阅读全文
摘要：
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... 阅读全文
摘要：
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 cli... 阅读全文
摘要：
Given two sorted integer arrays A and B, merge B into A as one sorted array. Note:You may assume that A has enough space (size that is greater or equa... 阅读全文
摘要：
Given a binary tree, return the level order traversal of its nodes' values. (ie, from left to right, level by level). For example:Given binary tree {3... 阅读全文
摘要：
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 le... 阅读全文
摘要：
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time.push(x) -- Push element x onto stack.pop() -- Removes... 阅读全文
摘要：
Write a program to find the node at which the intersection of two singly linked lists begins.For example, the following two linked lists: A: ... 阅读全文
摘要：
Given a binary tree, return the inorder traversal of its nodes' values. For example:Given binary tree {1,#,2,3}, 1 \ 2 / 3return [1,3,2]... 阅读全文