#include <iostream>
using namespace std;
// Variable declaration:
extern int a, b;
extern int c;
extern float f;

int main ()
{
 // Variable definition:
 int a, b;
 int c;
 float f;
 // actual initialization
 a = 10;
 b = 20;
 c = a + b;
 cout << c << endl ;
 f = 70.0/3.0;
 cout << f << endl ;
 return 0;
}