#include <iostream>
 using namespace std ;
 //This program created by instructor.

 int add( int x1 /* x1 */  , int x2 /* x2 */)
 {
	 //comment 1
	 return ( x1 + x2 ) ; //comment 2
	 //comment 3
 } //comment 4
 //comment 5
 /* comment 6 */ int main () //comment 7
 {
 	cout << "This program has comments." << endl ;
 	int x1 ;
 	cin >> x1 ;

 	return 0 ;

}