// z2.2-string
//
#include <iostream>
#include <string>
using namespace std;

int main()
{
  string s = "abcd";  cout << "s = " << s << ", length = " << s.length() << endl;

  cout << "s.at(1) = " << s.at(1) << endl;  s.at(1) = 'Z';  s.push_back('E');

  cout << "s = " << s << ", length = " << s.length() << endl;
}