specification of qsort :
qsort ( A , N , sizeof(Obj) , compare_function);
1. A is an array containing items you want to sort.
2. N is an integer , indicating how many items you want to sort.
3. If A is an array containing integers , you should fill in "sizeof(int)" as 3rd argument.
If A is an array containing many "Product" , you should fill in "sizeof(Product)" as 3rd argument
※Product can be a struct defined by anybody.
4. If you define a struct called "Product".
typedef struct
{
int Price;
int Size;
} Product;
You should implement the compare_function like this:
int compare_function1(const void *a, const void *b){
Product *c,*d;
c = (???) a;
d = (???) b;
if(..............) return -1; // Higher priority
else if (.................) return 1; // Lower priority
}
5. You may use "strcmp(name1,name2)" :
If name1 have higher priority , the function will return -1.
If name1 == name2 , the function will return 0.
If name 2 have higher priority , the function will return 1.