//////////////////////////////////////////////////
//  cstring.cpp - how do I use C style strings? //
//////////////////////////////////////////////////
#include <iostream>
#include <cstring>
using namespace std;

//  C language strings are arrays of chars 
//  always ending with a null char, e.g. '\0'

void main() {

  char *s1 = "this is the first string";

  cout << "\n  s1 = \"" << s1 << "\", its length is " 
       << strlen(s1) << '\n';
  cout << "  the third char is " << s1[2] << '\n';

  char s2[] = { 'a', 'e', 'i', 'o', 'u', '\0' };
  cout << "\n  s2 = \"" << s2 << "\", its length is " 
       << strlen(s2) << '\n';
  cout << "  the fourth char is " << s2[3] << '\n';

  char *s3 = new char[strlen(s1)+1];
  if(!s3)
    throw "\n  memory allocation failure\n\n";
  strcpy(s3,s1);
  cout << "\n  s3 is a copy of s1, e.g., \"" << s3 << "\"\n\n";
}