Thread: calling functions using pointers insteded of function names

I don't understand how a function pointer is used to call any function

I have written a program in which i have created four functons

Code:

 #include <stdlib.h>

void function1 ()
{
   printf("\n Hello ");	
}


void function2 ( int x)
{
	x = 2; 
	printf("\n x = %d ");	
}


int function3 ( int y)
{
	y = 2; 
	y++;
	return y;	
}


int function4 ()
{
	z = 2; 
	z++;
	return z;	
}


int main ()
{
	
return 0;	
}

I want to call each functions using pointers insteded of function names but I don't understand how to do it. mainly I am having trouble in type casting

Originally Posted by john.c

Code:

#include <stdio.h>
 
void function1()      { printf("Hello\n"); }
void function2(int x) { printf("x = %d\n", x); }
int  function3(int y) { return y + 1; }
int  function4()      { return 42; }
 
int main ()
{
    void (*f1)()    = function1;
    void (*f2)(int) = function2;
    int  (*f3)(int) = function3;
    int  (*f4)()    = function4;
 
    f1();
    f2(f3(f4()));
 
    return 0;   
}

understood, Thanks for the effort

Code:

#include <stdio.h>  
void function1()      { printf("Hello\n"); }
void function2(int x) { printf("x = %d\n", x); }
int  function3(int y) { return y + 1; }
int  function4()      { return 42; }
  
int main ()
{
	int a, b;
    void (*f1)()    = function1;
    void (*f2)(int) = function2;
    int  (*f3)(int) = function3;
    int  (*f4)()    = function4;
  
    a = f3(2);
    printf("a = %d\n", a); 
    b = f4();
	printf("b = %d\n", b); 
    return 0;   
}

a = 3
b = 42