Use pointers to functions as function arguments

One of the usual uses of function pointer variables is to pass pointers as parameters to other functions.

Examples of calling function pointers:

int int (*compare) (elemtype*, elemtype*))

Where compare is the function pointer name, (elemtype*, elemtype*) is the parameter of the function pointer.

Examples of calling function pointers:

if 0 )    return i;

The parameters &e1 and &e2 are two variables of type elemtype*.

Second, for example application

The Qsort function in Stdlib.h is often used in ACM competitions, in which there is a textbook-style function pointer application demonstration.

#include <stdio.h>#include<stdlib.h>intCompConst void*a,Const void*b) {    return*(int*) A-* (int*) b;}intMain () {intn =5; int*array = (int*)malloc(nsizeof(int)); inti =0;  for(; i<n; i++)    {        * (array + i) =Ten-i; } qsort (array, N,sizeof(int), comp);  for(i =0; i<n; i++) {printf ("%d\t", Array[i]); }    return 0;}

Use pointers to functions as function arguments