Week 6 (CS 200)

#include <iostream>
#include <iomanip>
#include <string>
using namespace std;

int main()
{
   bool   myBoolean = true;
   int    myInteger = 1;
   float  myFloat = 2.3;
   string myString = "Hello";

   cout << left;
   cout << setw( 15 ) << "VAR" << setw( 10 ) << "VALUE"
        << setw( 20 ) << "ADDRESS" << setw( 5 ) << "SIZE" << endl
       << string( 80, '-' ) << endl;

   cout << setw( 15 ) << "myBoolean" << setw( 10 ) << myBoolean
        << setw( 20 ) << &myBoolean << setw( 5 ) << sizeof( myBoolean ) << endl;

   cout << setw( 15 ) << "myInteger" << setw( 10 ) << myInteger
        << setw( 20 ) << &myInteger << setw( 5 ) << sizeof( myInteger ) << endl;

   cout << setw( 15 ) << "myFloat"   << setw( 10 ) << myFloat
        << setw( 20 ) << &myFloat   << setw( 5 ) << sizeof( myFloat )   << endl;

   cout << setw( 15 ) << "myString"  << setw( 10 ) << myString
        << setw( 20 ) << &myString  << setw( 5 ) << sizeof( myString )  << endl;

   return 0;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{
   string studentA = "Hikaru";
   string studentB = "Umi";
   string studentC = "Fuu";
   string* ptrTopStudent = nullptr; // Declare pointer

   bool done = false;

   while ( !done )
   {
       cout << "Students:" << endl
           << "A. " << studentA << "\t" << &studentA << endl
           << "B. " << studentB << "\t" << &studentB << endl
           << "C. " << studentC << "\t" << &studentC << endl << endl;

       cout << "Top student address: " << ptrTopStudent << endl;
       if ( ptrTopStudent != nullptr ) {
           // De-reference pointer
           cout << "Top student name: " << *ptrTopStudent << endl;
       }

       cout << endl << "Set top student to who? (A, B, C, or Q to quit): ";
       char choice;
       cin >> choice;

       switch( choice ) {
           // Assign pointer to address of variable
           case 'A': ptrTopStudent = &studentA; break;
           case 'B': ptrTopStudent = &studentB; break;
           case 'C': ptrTopStudent = &studentC; break;
           case 'Q': done = true; break;
           default: cout << "Invalid selection" << endl;
       }
   }

   return 0;
}

#include <iostream>
#include <string>
using namespace std;

struct Student
{
   string name;
   int grade;
};

int main()
{
   const int STUDENT_COUNT = 2;
   Student students[STUDENT_COUNT];
   Student* ptrCurrent;

   for ( int i = 0; i < STUDENT_COUNT; i++ )
   {
       ptrCurrent = &students[i];

       cout << "Enter a name: ";
       cin >> ptrCurrent->name;

       cout << "Enter the grade: ";
       cin >> ptrCurrent->grade;
   }

   for ( int i = 0; i < STUDENT_COUNT; i++ )
   {
       ptrCurrent = &students[i];
       cout << "NAME:  " << ptrCurrent->name << endl;
       cout << "GRADE: " << ptrCurrent->grade << endl;
   }

   return 0;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{
   int* myInteger;
   myInteger = new int;

   (*myInteger) = 30;

   cout << "Address of new integer: " << myInteger << endl;
   cout << "Value of new integer:   " << (*myInteger) << endl;

   delete myInteger; // Free the memory
   myInteger = NULL; // Reset the pointer to no address

   return 0;
}

#include <iostream>
#include <string>
using namespace std;

int main()
{
   // First array
   string* names = new string[ 5 ];
   names[0] = "Snake";
   names[1] = "Ocelot";
   names[2] = "Octopus";
   names[3] = "Fox";
   names[4] = "Wolf";

   // Oops, need more space...
   // Create a temporary array with a bigger size:
   string* newArray = new string[ 10 ];

   // Copy over the contents of the old array:
   for ( int i = 0; i < 5; i++ )
   {
       newArray[i] = names[i];
   }

   // Delete the old array, free that memory:
   delete [] names;

   // But, we still want to use the original array name.
   // So, we will change pointers!
   // Point "names" to the new, bigger array,
   // and reset our temporary array to NULL.

   names = newArray;
   newArray = NULL;

   // Now we can keep using the original names array
   names[5] = "Raven";
   names[6] = "Mantis";
   names[7] = "Fortune";
   names[8] = "Vamp";
   names[9] = "Fatman";

   // Output the results! :)
   for ( int i = 0; i < 10; i++ )
   {
       cout << (i+1) << ": " << names[i] << endl;
   }

   // Don't forget that we need to delete
   // the bigger array once the program ends.
   // names is currently pointing to the big array.
   delete [] names;

   return 0;
}