daoleno

每个阶段只有一个状态->递推；

每个阶段的最优状态都是由上一个阶段的最优状态得到的->贪心；

每个阶段的最优状态是由之前所有阶段的状态的组合得到的->搜索；

每个阶段的最优状态可以从之前某个阶段的某个或某些状态直接得到而不管之前这个状态是如何得到的->动态规划。

daoleno

To ensure that the names declared in that portion of code have C linkage, and thus C++ name mangling is not performed

#ifdef __cplusplus
extern "C" {
#endif

void *memset (void *, int, size_t);
char *strcat (char *, const char *);
int   strcmp (const char *, const char *);
char *strcpy (char *, const char *);

daoleno

void F(int);                     // 1: declaration of F(int)
void F(const int);               // 2: re-declaration of F(int)
void F(int) { /* ... */ }        // 3: definition of F(int)
void F(const int) { /* ... */ }  // 4: error: re-definition of F(int)

void F(const int* x);                  // 1
void F(const int& x); // 2

daoleno

• repr 可以打印出换行符之类的，是开发用的string类型，《fluent python》里有专门的介绍
• str 普通的字符串

Difference between str and repr in Python

daoleno

1. 虚拟机网络为 NAT 模式
2. 将虚拟机内代理设置成主机IP，端口为shadowsocks端口（1080）
3. shadowsocks 选中 允许来自局域网的链接

daoleno

(* move n discs from a to z (using third peg named x) *)
    let rec hanoi move n a z x = if n = 0 then () else 
      (hanoi move (n-1) a x z ; move n a z ; hanoi move (n-1) x z a)
    let printmove disc a b = print_endline 
        ("Move disc " ^ (string_of_int disc) ^ " from " ^ a ^ " to " ^ b) ;;
    hanoi printmove 4 "peg A" "peg C" "peg B"

daoleno

typedef struct X { 
    int x; 
} X;

struct S { 
    int x; 
};
typedef struct S S;

daoleno

Server

strace -r -e trace=bind,listen,accept,poll,read,write nc -l -p 8080 

Client

strace -r -e trace=connect,poll,read,write,close nc 127.0.0.1 8080

daoleno

• Compilation of source language into VM specific bytecode
• Data structures to contains instructions and operands (the data the instructions process)
• A call stack for function call operations
• An ‘Instruction Pointer’ (IP) pointing to the next instruction to execute
• A virtual ‘CPU’ – the instruction dispatcher that
  • Fetches the next instruction (addressed by the instruction pointer)
  • Decodes the operands
• Executes the instruction

daoleno

Step 1. Choose the concept you want to understand.

Take a blank piece of paper and write that concept at the top of the page.

Step 2. Pretend you’re teaching the idea to someone else.

Write out an explanation of the topic, as if you were trying to teach it to a new student. When you explain the idea this way you get a better idea of what you understand and where you might have some gaps.

Step 3. If you get stuck, go back to the book.

Whenever you get stuck, go back to the source material and re-learn that part of the material until you get it enough that you can explain it on paper.

Step 4. Simplify your language.