北叶青藤

摘要： Given an array of integers where 1 ≤ a[i] ≤ n (n = size of array), some elements appear twice and others appear once. Find all the elements of [1, n] 阅读全文

摘要： 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? 阅读全文

摘要： Determine whether an integer is a palindrome. Do this without extra space. 分析：把一个数倒过来，然后看两个数是否相同。 Reverse digits of an integer. Example1: x = 123, ret 阅读全文

摘要： Given a singly linked list, group all odd nodes together followed by the even nodes. Please note here we are talking about the node number and not the 阅读全文

摘要： Suppose we abstract our file system by a string in the following manner: The string "dir\n\tsubdir1\n\tsubdir2\n\t\tfile.ext" represents: dir subdir1 阅读全文

摘要： Given two strings s and t, determine if they are isomorphic. Two strings are isomorphic if the characters in s can be replaced to get t. All occurrenc 阅读全文

摘要： Question: For each word, you can get a list of neighbor words by calling getWords(String), find all the paths from word1 to word2. 阅读全文

摘要： Given a binary tree, check whether it is a mirror of itself (ie, symmetric around its center). For example, this binary tree [1,2,2,3,4,4,3] is symmet 阅读全文

摘要： Given two Binary Search Trees, find common nodes in them. In other words, find intersection of two BSTs. Example: from: http://www.geeksforgeeks.org/p 阅读全文

摘要： Given a string of numbers and operators, return all possible results from computing all the different possible ways to group numbers and operators. Th 阅读全文