#include <iostream>
using namespace std;


/**
 * This illustrates some basic string functionality and usage of the 4 functions created
 * in class.
 */
int main()
{
  // strlen
  {
    cout << endl
	 << "strlen\n------\n";

    // notice the '\0' 0-byte string terminating character
    char s[100] = {'h','e','l','l','o','\0'};
    
    // This is how you could print the string character by character,
    // looping until we see the '\0'
    cout << "Print string in for loop: ";
    for (int i=0; s[i] != '\0'; i++) {
      cout << s[i];
    }
    
    cout << endl
	 << "Print string using cout : " << s << endl;
    
    cout << endl
	 << "Print string length, notice that even " << endl
	 << "though the array is of size 100, the " << endl
	 << "answer is the number of chars before \'\\0\'" << endl << endl;

    cout << "strlen: " << strlen(s) << endl;
  }


  // strcpy
  {
    cout << endl
	 << "strcpy\n------\n";

    char dest[50]= "hello";
    char origin[5 + 1] = "world";
    
    cout << "Before: " << dest << endl;
    strcpy(dest,origin);
    cout << "After : " << dest << endl;    
  }

  // strcat
  {
    cout << endl
	 << "strcat\n------\n";

    char dest[50]= "hello";
    char origin[5 + 1] = "world";
    
    cout << "Before: " << dest << endl;
    strcat(dest,origin);
    cout << "After : " << dest << endl;    
  }

  // strcmp
  // Please notice all the different ways we create strings here.
  {
    cout << endl
	 << "strcmp\n------\n";

    cout << "A return of 0 means the strings are equal, \n" 
	 << "any other values means they are not."
	 << endl << endl;
    char s1[50]= "hello";                     // initializing using string
    char s2[50]= {'h','e','l','l','o','\0'};  // initialize using array

    // they are equivalent!
    cout << "Compare [" << s1 << "] and [" << s2 << "]: " <<  strcmp(s1,s2) << endl ;
    
    
    cout << "[Remove the \'\\0\'] from the second string: ";
    s2[5] = ' ';
    cout <<  strcmp(s1,s2) << endl;

    // Now compare two totally different strings
    s2[0] = 'w';
    s2[1] = 'o';
    s2[2] = 'r';
    s2[3] = 'l';
    s2[4] = 'd';
    s2[5] = '\0';

    cout << "Compare [" << s1 << "] and [" << s2 << "]: " <<  strcmp(s1,s2) << endl ;
    
    

  }

  cout << endl;
   
  return 0;
  
  

}