penggunaan fungsi pada c++

#include<iostream.h>

#include<conio.h>

void gaya(double m, double a); //prototype function

void main() //main function

{

double m,a;

cout<<"Massa : "; cin>>m;

cout<<"percepatan : "; cin>>a;

cout<<"F : ";

gaya(m,a); //parameter aktual

getch();

}

void gaya(double m, double a) //function definition

{

double hasil;

hasil=m*a;

cout<<hasil;

}