#include<stdio.h>


void B(int a, int b, int c){
    printf("B: a=%d, b=%d, c=%d\n", a, b, c);
    return ;
}

void* freturn(){
	return B;
}
void A(int a, int b, int c, int d){
    void (*fp)(int, int, int);
    fp = freturn();

    printf("A: a=%d, b=%d, c=%d, d=%d\n", a, b, c, d);
    return fp(a, b, c+d);
    //return B(a, b, c+d);
}

int main(int argc, char **argv){
    printf("main: \n");
    //fp = B;
    A(10, 20, 30, 40);
    return 0;
}