摘要：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... 阅读全文

摘要：Given a linked list, determine if it has a cycle in it.Follow up:Can you solve it without using extra space?Cracking Interview书上原题，快慢指针，如果有环肯定相遇。/** *... 阅读全文

摘要：Given a linked list, return the node where the cycle begins. If there is no cycle, returnnull.Follow up:Can you solve it without using extra space?Cra... 阅读全文

摘要：Given a singly linked listL:L0→L1→…→Ln-1→Ln,reorder it to:L0→Ln→L1→Ln-1→L2→Ln-2→…You must do this in-place without altering the nodes' values.For exam... 阅读全文

摘要：Given a binary tree, return theinordertraversal of its nodes' values.For example:Given binary tree{1,#,2,3}, 1 \ 2 / 3return[1,3,2].Note... 阅读全文

摘要：Given a binary tree, return thepreordertraversal of its nodes' values.For example:Given binary tree{1,#,2,3}, 1 \ 2 / 3return[1,2,3].先pu... 阅读全文

摘要：Given a binary tree, return thepostordertraversal of its nodes' values.For example:Given binary tree{1,#,2,3}, 1 \ 2 / 3return[3,2,1].No... 阅读全文

摘要：Given a range [m, n] where 0 > 1; while (s != 0) { a |= s; s >>= 1; } return m&n&~a... 阅读全文

摘要：Design and implement a data structure for Least Recently Used (LRU) cache. It should support the following operations:getandset.get(key)- Get the valu... 阅读全文

摘要：Sort a linked list inO(nlogn) time using constant space complexity.Merge Sort./** * Definition for singly-linked list. * class ListNode { * int ... 阅读全文

摘要：Evaluate the value of an arithmetic expression inReverse Polish Notation.Valid operators are+,-,*,/. Each operand may be an integer or another express... 阅读全文

摘要：Given an input string, reverse the string word by word.For example,Given s = "the sky is blue",return "blue is sky the".Update (2015-02-12):For C prog... 阅读全文

摘要：Find the contiguous subarray within an array (containing at least one number) which has the largest product.For example, given the array[2,3,-2,4],the... 阅读全文

摘要：Suppose a sorted array is rotated at some pivot unknown to you beforehand.(i.e.,0 1 2 4 5 6 7might become4 5 6 7 0 1 2).Find the minimum element.You m... 阅读全文

摘要：Follow upfor "Find Minimum in Rotated Sorted Array":What ifduplicatesare allowed?Would this affect the run-time complexity? How and why?Suppose a sort... 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: a... 阅读全文

摘要：A peak element is an element that is greater than its neighbors.Given an input array wherenum[i] ≠ num[i+1], find a peak element and return its index.... 阅读全文

摘要：Given a positive integer, return its corresponding column title as appear in an Excel sheet.For example: 1 -> A 2 -> B 3 -> C ... 26 ->... 阅读全文

摘要：Given an array of sizen, find the majority element. The majority element is the element that appears more than⌊ n/2 ⌋times.You may assume that the arr... 阅读全文