摘要：
Given a digit string, return all possible letter combinations that the number could represent. A mapping of digit to letters (just like on the telepho 阅读全文
摘要：
Given two words (beginWord and endWord), and a dictionary's word list, find all shortest transformation sequence(s) from beginWord to endWord, such th 阅读全文
摘要：
public class Solution extends Reader4 { /** * @param buf Destination buffer * @param n Maximum number of characters to read * @return The number of characters read */ ... 阅读全文
摘要：
There are a row of n houses, each house can be painted with one of the k colors. The cost of painting each house with a certain color is different. Yo 阅读全文
摘要：
The day breaks down into 5, 45-minute sessions: 1 – Behavior Interview 1 – Machine Learning Research 1 – Machine Learning Practical Design and Archite 阅读全文
摘要：
Here is what each of your five interviews will focus on: Sample topics might include:Coding: Write clean, bug-free code that properly handles edge cas 阅读全文
摘要：
推荐系统设计 当一个做推荐系统的部门开始重视【数据清理，数据标柱，效果评测，数据统计，数据分析】这些所谓的脏活累活，这样的推荐系统才会有救。 推荐系统特征 首先需要明确的就是推荐系统的目标，一般来说不外乎以下几个： 用户满意性：首当其冲的，推荐系统主要就是为了满足用户的需求，因此准确率是评判一个推荐 阅读全文
摘要：
最大似然估计 （MLE） 最大后验概率（MAP） 1） 最大似然估计 MLE 给定一堆数据，假如我们知道它是从某一种分布中随机取出来的，可是我们并不知道这个分布具体的参，即“模型已定，参数未知”。例如，我们知道这个分布是正态分布，但是不知道均值和方差；或者是二项分布，但是不知道均值。 最大似然估计（ 阅读全文
摘要：
We are playing the Guess Game. The game is as follows: I pick a number from 1 to n. You have to guess which number I picked. Every time you guess wron 阅读全文
摘要：
Design a hit counter which counts the number of hits received in the past 5 minutes. Each function accepts a timestamp parameter (in seconds granulari 阅读全文
摘要：
Given a set of distinct positive integers, find the largest subset such that every pair (Si, Sj) of elements in this subset satisfies: Si % Sj = 0 or 阅读全文
摘要：
Design a simplified version of Twitter where users can post tweets, follow/unfollow another user and is able to see the 10 most recent tweets in the u 阅读全文
摘要：
SIFT特征检测主要包括以下4个基本步骤：[1] 尺度空间极值检测： 搜索所有尺度上的图像位置。通过高斯微分函数来识别潜在的对于尺度和旋转不变的兴趣点。 2. 关键点定位 在每个候选的位置上，通过一个拟合精细的模型来确定位置和尺度。关键点的选择依据于它们的稳定程度。 3. 方向确定 基于图像局部的梯 阅读全文
摘要：
Histogram of Oriented Gradients (HOG) Descriptor Histogram of oriented gradients (HOG) is a feature descriptor used to detect objects in computer visi 阅读全文
摘要：
The most common algorithm uses an iterative refinement technique. Due to its ubiquity it is often called the k-means algorithm; it is also referred to 阅读全文
摘要：
A binary watch has 4 LEDs on the top which represent the hours (0-11), and the 6 LEDs on the bottom represent the minutes (0-59). Each LED represents 阅读全文
摘要：
Find the sum of all left leaves in a given binary tree. Example: 阅读全文
摘要：
A group of friends went on holiday and sometimes lent each other money. For example, Alice paid for Bill's lunch for 10.ThenlaterChrisgaveAlice10.Then 阅读全文