Callback Function With Parameter Argument

#include <iostream>

/**

 * Callback function need two function:

 * 1. caller function - display();

 * 2. called function - hello();

 *

 * Caller function just a function that has task to call

 * the another function while the called function is 

 * what the function we define and we write.

 *

 * parameter supplied by the program or api. not you as programmer

 *

 */

using namespace std;

/**

 * This function is like main entry function

 */
void hello(int c){
    cout << c << endl;  // print out 45
}

void display(void(*func)(int)){
    int def = 45;
    func(def);
}

int main(int argc, char *argv[]){
    display(hello);
}

Callback Function With Parameter Argument