basic

1. about ponter

1. address(取地址): &b

2. dereference(解引用)；indirection(间接寻址)

   一个指针代表对变量的一次引用； 访问指针指向地址: *p=100

3. 引用操作: 赋值给指针

resource-bound:

the rate of the task is bound(decided) to resources in other words: it need many that resources. (resources 密集型)

types of bounds:

1. cpu-bound: cpu speed
2. i/o-bound：i/o speed
3. memory-bound: memory size and memory accessing speed

i/o bound:

1. the type of devices
2. the arhitecture of read/write file

do many task such as read/write file,, network

1. chat app;

cpu bound app: do many tasks such as caculations

1. photo editors
2. video editors