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公开课笔记
CMU 15-445/645 Database Systems
Relational Data Model
Advanced SQL
Database Storage
Buffer Pools
Hash Tables
Tree Indexes
Index Concurrency Control
Query Processing
Sorting&Aggregations
Join Algorithms
Query Optimization
Parallel Execution
Embedded Database Logic
Concurrency Control Theory
Two Phase Locking
Timestamp Ordering Concurrency Control
Multi-Version Concurrency Control
Logging Schemes
Database Recovery
Introduction to Distributed Databases
Distributed OLTP Databases
Distributed OLAP Databases
UCB - CS162
OS intro
Introduction to the Process
Processes, Fork, I/O, Files
I/O Continued, Sockets, Networking
Concurrency: Processes & Threads
Cooperating Threads, Synchronization
Semaphores, Condition Variables, Readers/Writers
Scheduling
Resource Contention & Deadlock
Address Translation, Caching
File System (18,19,20)
Distributed Systems, Networking, TCP/IP, RPC (21,22)
Distributed Storage, Key-Value Stores, Security (23)
Security & Cloud Computing (24)
Topic: Ensuring Data Reaches Disk
MIT - 6.006
Sequence and Set Interface
Data Structure for Dynamic Sequence Interface
Computation Complexity
Algorithms and Computation
Structure Of Computation
Graph & Search
Tree & Search
Weighted Shortest Paths
String Matching, Karp-Rabin
Priority Queue Interface & Implementation
Dictionary Problem & Implementation
Sorting
Dynamic Programming
Backtracking
Self-Balancing Tree
MIT - 6.824
2PC & 3PC
Introduction and MapReduce
RPC and Threads
Primary/Backup Replication
Lab: Primary/Backup Key/Value Service
Google File System (GFS)
Raft
Lab: Raft - Leader Election
Lab: Raft - Log Replication
Stanford-CS107
原始数据类型及相互转化
指鹿为马
泛型函数
泛型栈
运行时内存结构
从 C 到汇编
函数的活动记录
C 与 C++ 代码生成
编译的预处理过程
编译的链接过程
函数的活动记录续、并发
从顺序到并发和并行
信号量与多线程 1
信号量与多线程 2
复杂多线程问题
函数式编程 - Scheme 1
函数式编程 - Scheme 2
函数式编程 - Scheme 3
函数式编程 - Scheme 4
函数式编程 - Scheme 5
Python 基础
MIT - 6.001 - SICP
什么是程序
程序抽象
替代模型
时间/空间复杂度
数据抽象
高阶函数
Symbol
数据驱动编程与防御式编程
数据抽象中的效率与可读性
数据修改
环境模型
面向对象-消息传递
面向对象 - Scheme 实现
构建 Scheme 解释器
Eval-Apply Loop
Normal Order (Lazy) Evaluation
通用机
寄存器机器
子程序、栈与递归
在寄存器机器中执行
内存管理
MIT - 6.046
Randomized Algorithms
Skip Lists
System Design
Twitter
Cache Consistency & Coherence
DDIA 笔记
Replication
Transactions
The Trouble with Distributed Systems
Consistency & Consensus
Papers We Love
Consistent Hashing and Random Trees (1997)
Dynamic Hash Tables (1988)
LFU Implementation With O(1) Complexity (2010)
Time, Clocks, and the Ordering of Events in a Distributed System (1978)
Dapper, a Large-Scale Distributed Systems Tracing Infrastructure (2010)
Gorilla: A Fast, Scalable, In-Memory Time Series Database (2015)
Release It 笔记
Anti-patterns & Patterns in Microservice Architecture
Database Design
Log Structured Merge (LSM) Tree & Usages in KV Stores
Prometheus
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函数式编程 - Scheme 4
第二十二课
generate power set recursively
; ps => power-set
>
(
ps
'(
1
2
3
))
(()
(
2
)
(
3
)
(
2
3
)
; 不含 1 的集合
(
1
)
(
1
2
)
(
1
3
)
(
1
2
3
))
; 含 1 的集合
>
(
ps
'())
(())
(
define
(
ps
set
)
(
if
(
null?
set
)
'(())
(
append
(
ps
(
cdr
set
))
(
map
(
lambda
(
subset
)
(
cons
(
car
set
)
subset
))
(
ps
(
cdr
set
))))))
上面的实现非常的精简,就是把一个 set 的 power-set 看作是两部分的集合:
不含 set 第一个元素的 power-set (记为 ps-rest)
包含 set 第一个元素的 power-set (记为 ps-all)
其中 ps-all 可以看作是第一个元素与 ps-rest 之间的每个元素的分别取合的集合。但以上实现有一个缺点,就是
(ps (cdr set))
被执行了两次:
(
define
(
ps
set
)
(
if
(
null?
set
)
'(())
(
let
((
ps-rest
(
ps
(
cdr
set
))))
(
append
ps-rest
(
map
(
lambda
(
subset
)
(
cons
(
car
set
)
subset
))
ps-rest
)))))
这里的 let-binding 实际上是 lambda 的语法糖:
(
let
((
x
_x
))
((
y
_y
))
(
a
x y
))
; =>
((
lambda
(
x y
)
(
a
x y
))
_x _y
)
Permutation
>
(
permute
'(
1
2
3
))
((
1
2
3
)
(
1
3
2
)
(
2
1
3
)
(
2
3
1
)
(
3
1
2
)
(
3
2
1
))
(
define
(
permute
items
)
(
if
(
null?
items
)
'(())
(
apply
append
(
map
(
lambda
(
elem
)
(
map
(
lambda
(
permutation
)
(
cons
elem permutation
))
(
permute
(
remove
items elem
)))
items
))))
Scheme 中原始类型的存储举例
>
4
4
>
"hello"
hello
>
'(
1
2
3
)
(
1
2
3
)
>
(
cons
1
(
cons
2
(
cons
3
'())))
(
1
2
3
)
4、"hello"、'(1 2 3) 在内存中如下图所示:而
'(1 2 3)
实际上是
(cons (1 (cons 2 (cons 3 '())))
的语法糖。
Could not load image
参考
Stanford-CS107-lecture-22
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3yr ago
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