no 4

Program menghitung volume lingkaran

#include <cstdlib>
#include <iostream>
#include <conio.h>
using namespace std;
void luas(int r){
 int hasil,phi;
 phi=3,14;
 hasil=phi*r*r;
 cout<<"Hasil luas lingkaran : "<<hasil<<endl;
}
int main(int argc, char *argv[])
{
 int r;
 cout<<"|=========================|\n";
 cout<<"| Program Menghitung Luas |\n";
 cout<<"|        Lingkaran        |\n";
 cout<<"|=========================|\n";
 cout<<"Masukkan jari-jari : ";cin>>r;
 luas(r);
 system("pause");
 return 0;
}