摘要: 题目描述 Given two binary trees and imagine that when you put one of them to cover the other, some nodes of the two trees are overlapped while the others 阅读全文
posted @ 2017-07-06 18:21 legooooo 阅读(119) 评论(0) 推荐(0) 编辑
摘要: 题目描述: Given a binary tree, determine if it is height-balanced. For this problem, a height-balanced binary tree is defined as a binary tree in which th 阅读全文
posted @ 2017-07-06 17:00 legooooo 阅读(136) 评论(0) 推荐(0) 编辑
摘要: 题目描述 Given two strings s and t, write a function to determine if t is an anagram of s. For example,s = "anagram", t = "nagaram", return true.s = "rat" 阅读全文
posted @ 2017-06-29 16:23 legooooo 阅读(107) 评论(0) 推荐(0) 编辑
摘要: 题目描述: 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 阅读全文
posted @ 2017-06-27 20:53 legooooo 阅读(117) 评论(0) 推荐(0) 编辑
摘要: 题目描述: 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 阅读全文
posted @ 2017-06-26 16:32 legooooo 阅读(127) 评论(0) 推荐(0) 编辑
摘要: 题目描述: Say you have an array for which the ith element is the price of a given stock on day i. If you were only permitted to complete at most one trans 阅读全文
posted @ 2017-06-26 15:52 legooooo 阅读(129) 评论(0) 推荐(0) 编辑
摘要: 题目描述: You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopp 阅读全文
posted @ 2017-06-26 15:47 legooooo 阅读(95) 评论(0) 推荐(0) 编辑
摘要: Description: Given an integer array nums, find the sum of the elements between indices i and j (i ≤ j), inclusive. Example: Note: 这是一个比较简单的元素相加题目。给定一个 阅读全文
posted @ 2017-06-26 15:40 legooooo 阅读(142) 评论(0) 推荐(0) 编辑
摘要: 转载一篇文章 如何在 Kaggle 首战中进入前 10% Posted on 2016-04-29 | In Data Science | Introduction 本文采用署名 - 非商业性使用 - 禁止演绎 3.0 中国大陆许可协议进行许可。著作权由章凌豪所有。 Kaggle 是目前最大的 Da 阅读全文
posted @ 2017-05-25 18:30 legooooo 阅读(587) 评论(0) 推荐(0) 编辑
摘要: 随机森林 RF RandomForest 随机森林的集成学习方法是bagging ,但是和bagging 不同的是bagging只使用bootstrap有放回的采样样本,但随机森林即随机采样样本,也随机选择特征,因此防止过拟合能力更强,降低方差。 使用的融合方法:bagging 一种集成学习算法,基 阅读全文
posted @ 2017-05-24 19:16 legooooo 阅读(15908) 评论(0) 推荐(1) 编辑