# Introduction

## Part I - PHP

* [开发环境](part-i-php/de)
  * [安装扩展](part-i-php/de/extensions)
* [原码反码补码](part-i-php/yuan-ma-fan-ma-bu-ma)
* [位运算](part-i-php/wei-yun-suan)

## Part II - 前端开发笔记

* [前端开发笔记](part-ii-qian-duan-kai-fa-bi-ji/web)
  * [Nodejs](part-ii-qian-duan-kai-fa-bi-ji/web/nodejs)
    * [开发环境](part-ii-qian-duan-kai-fa-bi-ji/web/nodejs/de)
  * [Echarts](https://github.com/qqqwed/study/tree/23bd4a522c6e635606a4d26a4b9bd4f6936391a1/WEB/echarts.md)

## Part III - 数据结构与算法

* [复杂度速查表](part-iii-shu-ju-jie-gou-yu-suan-fa/fu-za-du-su-cha-biao)
* 剑指 offer 题解
  * [数组中重复的数字](part-iii-shu-ju-jie-gou-yu-suan-fa/jian-zhi-offer-ti-jie/shu-zu-zhong-zhong-fu-de-shu-zi)

## Part IV - 解决方案

* [单点登录（Single Sign On）解决方案](part-iv-jie-jue-fang-an/sso)
* [前端常见跨域解决方案 (全)](part-iv-jie-jue-fang-an/cf)
