xclfafa的博客

题目：You are standing at position 0 on an infinite number line. There is a goal at position target.On each move, you can either go left or right. During the n-th move (starting from 1), you take n steps...

题目：Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive.The update(i, val) function modifies nums by updating the element at index i to val.

题目：Given a sequence of n integers a1, a2, ..., an, a 132 pattern is a subsequence ai, aj, ak such that i j k and ai < ak j. Design an algorithm that takes a list of n numbers as input

题目：Given a binary search tree, write a function kthSmallest to find the kth smallest element in it.Note: You may assume k is always valid, 1 ≤ k ≤ BST's total elements.void f(vector &r

题目：Given a collection of intervals, find the minimum number of intervals you need to remove to make the rest of the intervals non-overlapping.Note:You may assume the interval's end poi

题目：Description:Count the number of prime numbers less than a non-negative number, n.思路：暴力求解是一种，还有就是筛选法，创建一个n的数组，初始化为true，遍历开始，就是当i是质(素)数的时候，i的所有的倍数必然是合数。如果i已经被判断不是质数了，那么再找到i后面的质数来把这个质数的倍

题目：Given a non-empty integer array of size n, find the minimum number of moves required to make all array elements equal, where a move is incrementing n - 1 elements by 1.Example:Input:[1

题目：198. House RobberYou are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each

题目：Given a sorted positive integer array nums and an integer n, add/patch elements to the array such that any number in range [1, n] inclusive can be formed by the sum of some elements in the

题目：Given an array nums containing n + 1 integers where each integer is between 1 and n (inclusive), prove that at least one duplicate number must exist. Assume that there is only one duplicate n

题目：Given two strings A and B, find the minimum number of times A has to be repeated such that B is a substring of it. If no such solution, return -1.For example, with A = "abcd" and B = "cda

题目：Given an integer array of size n, find all elements that appear more than ⌊ n/3 ⌋ times. The algorithm should run in linear time and in O(1) space.思路：http://www.cnblogs.com/grandyang/p/4606

题目：Given an array of non-negative integers, you are initially positioned at the first index of the array.Each element in the array represents your maximum jump length at that position.De

题目：In English, we have a concept called root, which can be followed by some other words to form another longer word - let's call this word successor. For example, the root an, followed by othe

题目：Suppose you have N integers from 1 to N. We define a beautiful arrangement as an array that is constructed by these N numbers successfully if one of the following is true for the ith position (1 &l...

题目：Given an integer matrix, find the length of the longest increasing path.From each cell, you can either move to four directions: left, right, up or down. You may NOT move diagonally or move outside ...

题目：A move consists of taking a point (x, y) and transforming it to either (x, x+y) or (x+y, y).Given a starting point (sx, sy) and a target point (tx, ty), return True if and only if a sequence of mov...

题目：Given a string, your task is to count how many palindromic substrings in this string.The substrings with different start indexes or end indexes are counted as different substrings even th

题目：Given an integer n, count the total number of digit 1 appearing in all non-negative integers less than or equal to n.For example:Given n = 13,Return 6, because digit 1 occurred in the

题目：Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation.

题目：Given a circular array (the next element of the last element is the first element of the array), print the Next Greater Number for every element. The Next Greater Number of a number x is the

题目：Given a string s, partition s such that every substring of the partition is a palindrome.Return the minimum cuts needed for a palindrome partitioning of s.For example, given s = "aab",R

题目：Given a list of 24-hour clock time points in "Hour:Minutes" format, find the minimum minutes difference between any two time points in the list.Example 1:Input: ["23:59","00:00"]Outp

题目：Given a non-empty array containing only positive integers, find if the array can be partitioned into two subsets such that the sum of elements in both subsets is equal.Note:Each of

题目：Given a binary tree, find the leftmost value in the last row of the tree.void f(TreeNode* root,int cur,vector>& re){ if(root !=NULL){ if(cur < re.size()){ re[cur].push

raw blog：http://blog.youkuaiyun.com/corpsepiges/article/details/52573281 题目：There is a list of sorted integers from 1 to n. Starting from left to right, remove the first number and every other numbe

题目：Given a string, sort it in decreasing order based on the frequency of characters.Example 1:Input:"tree"Output:"eert"Explanation:'e' appears twice while 'r' and 't' both appear on

题目：You have n super washing machines on a line. Initially, each washing machine has some dresses or is empty.For each move, you could choose any m (1 ≤ m ≤ n) washing machines, and pass one

题目：The demons had captured the princess (P) and imprisoned her in the bottom-right corner of a dungeon. The dungeon consists of M x N rooms laid out in a 2D grid. Our valiant knight (K) was init

题目：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 contiguous subarray [2,3] has the

题目：Given a linked list, return the node where the cycle begins. If there is no cycle, return null.思路：快慢指针的使用。首先，first为快指针，每次只走一步；second为慢指针，每次走两步；快慢指针同时开始遍历，当快慢指针相等时，说明有环。并且，假设链表开始到环起点长为 s，环长为 l；当se

题目：Given a singly linked list L: 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 example,Given {1,2,3,4}, reord

题目·：Given a non negative integer number num. For every numbers i in the range 0 ≤ i ≤ num calculate the number of 1's in their binary representation and return them as an array.思路：对于前n为的数如果已经统

题目：In the computer world, use restricted resource you have to generate maximum benefit is what we always want to pursue.For now, suppose you are a dominator of m 0s and n 1s respectively.

题目：There are N gas stations along a circular route, where the amount of gas at station i is gas[i].You have a car with an unlimited gas tank and it costs cost[i] of gas to travel from statio

题目：Given a positive integer n, find the number of non-negative integers less than or equal to n, whose binary representations do NOT contain consecutive ones。思路：对于每个数的二进制表示，假设这个数有n位。令f(n) 表示从右到左第n

题目：Given an array with n objects colored red, white or blue, sort them so that objects of the same color are adjacent, with the colors in the order red, white and blue.Here, we will use the in

题目：Given a 2D binary matrix filled with 0's and 1's, find the largest square containing only 1's and return its area.For example, given the following matrix:1 0 1 0 01 0 1 1 11 1 1 1 11

题目：Given an encoded string, return it's decoded string.The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note

题目：Given inorder and postorder traversal of a tree, construct the binary tree.Note:You may assume that duplicates do not exist in the tree.class Solution {public: TreeNode* f(v