can someone step by step comment and explain the logic of the code.

specailly when its return -1 ?

#include

#include

#include

using namespace std;

struct FIELDS

{

string name;

string value;

};

const int cnt = 4;

class WebApps {

private:

string qs; // holds the QUERY_STRING

int cnt; // holds the number of fields found from the form

public: //public access specifier.

WebApps (){ //constructor

cout << "Content-type:text/html "; //get ready to print on browser

set_qs(getenv("QUERY_STRING")); //save string to private qs

cout << "debug with get_qs: " << get_qs(); //testing functions

set_cnt(how_many(get_qs()));

cout << " debug with get_cnt: " << get_cnt();//testing functions

}

void set_qs (string f_getenv)

{

qs = f_getenv;

}

void set_cnt(int f_how_many)

{

cnt=f_how_many;

}

string get_qs()

{

return qs;

}

int get_cnt()

{

return cnt;

}

//////////////////////////////////////////////////// // how_many() // This will count how many = signs in the QUERYSTRING ////////////////////////////////////////////////////

int how_many(string f_qs)

{

int start_pos = 0, pos, count = 0;

do

{

pos = f_qs.find ("=", start_pos);

count++;

start_pos = pos + 1;

}

while (pos != string::npos);

return count - 1;

}

////////////////////////////////////////////////////

//create_array

// Creates a dynamic array

////////////////////////////////////////////////////

FIELDS *create_array (int f_cnt)

{

FIELDS *array= new FIELDS [f_cnt]; //creating the dynamic array

return array;

}

/////////////////////////////////////////////

// parse()

// This will separate the name/value pairs found after the ? in the URL

/////////////////////////////////////////////

void parse (string f_qs, FIELDS f_name_value_pairs [])

{

string name, value;

int start_pos = 0, pos;

for (int counter=0; counter < cnt; counter++) {

pos = qs.find("=", start_pos);

name = qs.substr(start_pos, pos - start_pos);

start_pos = pos + 1;

pos = qs.find("&", start_pos);

if (pos == string::npos) {

pos = qs.length();

}

value = qs.substr(start_pos, pos - start_pos);

start_pos = pos + 1;

FIELDS field = {name, value};

f_name_value_pairs[counter] = field;

if (pos == qs.length()){

return;

}

}

}

/////////////////////////////////////////////

// param()

// Will receive the value for any given form field

/////////////////////////////////////////////

string param(string lookUp, FIELDS f_name_value_pairs[], int f_cnt)

{

for (int counter=0; counter < f_cnt; counter++) {

if (f_name_value_pairs[counter].name == lookUp){

return f_name_value_pairs[counter].value;

}

}

return "";

}

};

int main()

{

WebApps wo; // name the class object

FIELDS name_value_pairs [cnt];

string qs;//(getenv("QUERY_STRING"));

cout << "Content-type:text/html ";

wo.parse(qs, name_value_pairs);

string first = wo.param("first", name_value_pairs, cnt);

string last = wo.param("last", name_value_pairs, cnt);

string color =wo.param("color", name_value_pairs, cnt);

string witch =wo.param("witch", name_value_pairs, cnt);

string about =wo.param("about", name_value_pairs, cnt);

cout<<"";

cout<<"";

cout<<"

";

cout<<"";

cout<<"

FirstName: "<

LastName :"<

"<<"About:"<

";

cout<<"

"<

return 0;

}