Programming Paradigm Episode3 and 4

Episode 3

--storage structure. Ampersand operate with Asterisk

--library function

Episode 4

--generic function Generic Functions

Swap (void* pa,void*pb,int size);

-----Ampersand and asterisk

The original types does not matter much, the pointer does.

When a pointer was operated with a intergral, just remember to transit the intergral into the same type length with the POI Nter.

--big endian, Little endian (most Linux)

-----array

int array[10];

Array = &arry[0];

Array+k = &array[k]; K for pointer operation, to expand to array of the same type length

*array = array[0];

* (ARRAY+K) =array[k];

* (array-4) = 8;

ARRAY[-4] = 8;//there is no bond check in C, so it'll put 8 at the corresponding address. This isn't good//code, the result is unsure, it may crush.

-------liabrary function

--strdup ("ADM"); As it shows itself, only valid to string type.

memcpy Function,return An adress pointed at the heap which store "ADM" (with string end sign).

--strcpy (Paim, "4021");
"4021" is copied to the memory started at address Paim.

--memcpy (void*to,void*from,int size)
Copy designated size to the memory.

------Swap (void* pa,void*pb,int size);

Swap (void* pa,void*pb,int size) {    char temp[size];    memcpy (temp,pa,size);    memcpy (pa,pb,size);    memcpy (pb,temp,size);} 

Programming Paradigm Episode3 and 4