#include <string>
#include <iostream>
using namespace std;

int main() {

  string s,p;
  cout << "capa : " << s.capacity() << " size: " << s.size() << endl;
  cin >> s >> p;
  cout << "capa : " << s.capacity() << " size: " << s.size() << endl;
  cout << s << p << endl;

  if (s.empty()) cout << "s e' vuota" << endl;

  s.append("HEllo world");
  if (s.empty()) cout << "s e' vuota" << endl;
  else {
    cout << "S e' " << s << endl;
  }
  cout << "size " << s.size() << endl;

  return 0;
}