switch, case help

In this code I got case, 1, 2, 3 in the switch, but I am having trouble with 4 and 5.

Code:

---


#include <iostream>
#include <list>
#include <NewString.h> // NewString class definition

using namespace std;   

// display program instructions to user
void instructions()
{
  cout << "Enter one of the following:\n"
  <<"  1 to create a NewString from a char*\n"
  <<"  2 to display the current NewString\n"
  <<"  3 to concatenate a second NewString to the current NewString\n"
  <<"  4 to show the length of the current NewString\n"
  <<"  5 to find out if a given NewString is substring if the current NewString\n";
 
} // end function instructions

void main()
{ 
  cout << "Testing a string of characters " <<". \n";

  instructions();  // display instructions

  int    choice;
  char value[100];

  NewString*  pCurString = NULL;
 
  do {
      cout << "Enter choice (0 to quit)? ";
      cin >> choice;
     
    switch ( choice )
    {
        case 1:
            cout << "Enter a text string: ";
            cin >> value;
           
            if (pCurString != NULL)
                delete pCurString; 
            pCurString = new NewString(value);           
            break;
        case 2:
            if (pCurString != NULL)
            {                                           
                cout << "Current NewString = ";
                pCurString->display();
                cout << endl << endl;
            }
            break;
        case 3:  // concatenate string
            if (pCurString != NULL)
            {                                         
                cout << "Current NewString = ";
                pCurString->display();
                cout << endl << endl;
                cout << "Enter string/character to concatenate = ";
                char cinput[64];
                cin >> cinput;

                if (strlen(cinput) != 1)
                {
                    NewString ns(cinput);
                    pCurString->concatenate(ns);  // append a string
                }
                else
                {
                    pCurString->concatenate(cinput[0]);  // append a single char
                }
                case 4:
                case 5:
        }
            break; 

      } // end switch


    }while ( choice != 0 ); 
                            // end do/while

  cout << "End list test\n\n";


}

---

what seems to be the problem i don't even see anything listed in your case 3 & 4?

Actully now that i look at it you need to change this before you even add anything

Code:

---

case 3:  // concatenate string
            if (pCurString != NULL)
            {                                         
                cout << "Current NewString = ";
                pCurString->display();
                cout << endl << endl;
                cout << "Enter string/character to concatenate = ";
                char cinput[64];
                cin >> cinput;

                if (strlen(cinput) != 1)
                {
                    NewString ns(cinput);
                    pCurString->concatenate(ns);  // append a string
                }
                else
                {
                    pCurString->concatenate(cinput[0]);  // append a single char
                }
                case 4:
                case 5:

---

To This

Code:

---

case 3:  // concatenate string
            if (pCurString != NULL)
            {                                         
                cout << "Current NewString = ";
                pCurString->display();
                cout << endl << endl;
                cout << "Enter string/character to concatenate = ";
                char cinput[64];
                cin >> cinput;

                if (strlen(cinput) != 1)
                {
                    NewString ns(cinput);
                    pCurString->concatenate(ns);  // append a string
                }
                else
                {
                    pCurString->concatenate(cinput[0]);  // append a single char
                }
            }//<----------------Added This
              break;//<------And this
                case 4:
                case 5:

---

Case 4 and 5 weren' t there because I am trying to figure out how to do it. I have made an attempt at 4, but not sure how to show the length :confused:
Case 5, I have no idea how to start that one!
Need help, thanks!!

Code:

---


#include <iostream>
#include <list>
#include <NewString.h> // NewString class definition

using namespace std;   

// display program instructions to user
void instructions()
{
  cout << "Enter one of the following:\n"
  <<"  1 to create a NewString from a char*\n"
  <<"  2 to display the current NewString\n"
  <<"  3 to concatenate a second NewString to the current NewString\n"
  <<"  4 to show the length of the current NewString\n"
  <<"  5 to find out if a given NewString is substring if the current NewString\n";
 
} // end function instructions

void main()
{ 
  cout << "Testing a string of characters " <<". \n";

  instructions();  // display instructions

  int    choice;
  char value[100];

  NewString*  pCurString = NULL;
 
  do {
      cout << "Enter choice (0 to quit)? ";
      cin >> choice;
     
    switch ( choice )
    {
        case 1:
            cout << "Enter a text string: ";
            cin >> value;
           
            if (pCurString != NULL)
                delete pCurString; 
            pCurString = new NewString(value);           
            break;
        case 2:
            if (pCurString != NULL)
            {                                           
                cout << "Current NewString = ";
                pCurString->display();
                cout << endl << endl;
            }
            break;
        case 3:  // concatenate string
            if (pCurString != NULL)
            {                                         
                cout << "Current NewString = ";
                pCurString->display();
                cout << endl << endl;
                cout << "Enter string/character to concatenate = ";
                char cinput[64];
                cin >> cinput;

                if (strlen(cinput) != 1)
                {
                    NewString ns(cinput);
                    pCurString->concatenate(ns);  // append a string
                }
                else
                {
                    pCurString->concatenate(cinput[0]);  // append a single char
                }
            }
           
            break;
          case 4:
                    if (pCurString != NULL)
                    {
                      cout << "NewString length = ";
                      pCurString->cinput();
                cout << endl << endl;
            }
            break;
           
          case 5: 
              if (pCurString != NULL)
              {
             
            }
            break;

      } // end switch


    }while ( choice != 0 ); 
                            // end do/while

  cout << "End list test\n\n";


}

---

Still trying to figure out how to show the length in case 4:
In case 5: returns 1 (true) if string2 is a substring of string1 and 0 (false). How do I do an if with a substring?
Does anybody know this stuff? :eek:

Thanks!!

Is NewString a class you wrote?
As for #4, there should either be a size variable in the class or you should have a way of searching through the string to the end (when a null character is reached, for example). I don't know without seeing that class, though.

Is this what you are looking for? Obviously I had help with this!!

Code:

---

#ifndef NEWSTRING_H
#define NEWSTRING_H
#include <list>
#include <iostream>

using namespace std;

class NewString
{
private:
    list<char> m_chars;
   
public:
    NewString()  {}
    NewString(const char* psz) {  while (*psz != 0) { m_chars.push_back(*psz); psz++; } }
    ~NewString() {}
   
    NewString& concatenate(const NewString& string2)
    { m_chars.insert(m_chars.end(), string2.m_chars.begin(), string2.m_chars.end()); return *this; }
    NewString& concatenate(char c) { m_chars.push_back(c); return *this; }
    const char* getText(char* buf, size_t sizBuf) 
    {
        int i = 0;
        for (list<char>::iterator it = m_chars.begin(); it != m_chars.end(); ++it)
            buf[i++] =*it;
        buf[i] = '\0';
        return buf;
    }
    void            display()
    {
        for (list<char>::iterator it = m_chars.begin(); it != m_chars.end(); ++it)
            cout << *it;
    }
    int            length()    { return (int)m_chars.size(); }
    bool            is_substring(const NewString& string2)   
    {
        char* pBuf = new char[m_chars.size()+1];
        getText(pBuf, m_chars.size()+1) ;
        char* pStr = new char[string2.m_chars.size()+1];
        getText(pStr, string2.m_chars.size()+1) ;
        bool ret = false;
        if (strstr(pBuf, pStr) != NULL)
            ret = true;
        delete [] pBuf; 
        delete [] pStr; 
    }
   
};
 
#endif // NEWSTRING_H

---

Hmmm.... NewString has a length() function and an is_substring(const NewString& string2) function. Step one is to try to use those to solve your problem. Since the substring problem requires a second string (the substring to lookup), you might have to ask the user to input the second string in case 5.