#include <iostream.h>
#include <fstream.h>
#include "vector.h"
#include "CPstring.h"

// file: tagsort.cc
// author      Dietolf Ramm;  date: 12/5/96
// illustrate new
// illustrate use of vector of pointers

   struct who
   {
      string name;
      int zip;
   };

void GetData(Vector<who *> & tags, int & size)
// precondition: Empty vector of pointers to who: tags
//    File "TagData" with lines containing a zipcode followed by a name
// postcondition: struct of type who allocated for each line in
//   file "TagData" with zip and name stored.  Vector tags contains
//   pointers to each of the structs.  size contains number of structs
//   (== number of vector elements used)
{
   int code, k=0;

   ifstream datain("TagData");
   while ( datain >> code)
   {
      tags[k] = new who;
      tags[k] -> zip = code;
      getline(datain, tags[k] -> name);
      k++;
   }
   size = k;
}

void ShowData(const Vector<who *> & tags, int size)
// precondition: tags contains pointers to size structs containing
//   data fields zip and name.
// postcondition: zip and name fields printed out in order dictated
//   by the order of the pointers in tags
{
   int k;

   for (k = 0; k < size; k++)
   {
      cout << tags[k]->name << ", " << tags[k] -> zip << endl;
   }
}

void SelectTagSortZip(Vector<who *> & tags, int size)
// precondition: tags contains pointers to size structs containing
//   data fields zip and name.
// postcondition: tags entries sorted so as to point to structs
//   in ordeer by zip
{
   int k, j, minindex;
   who * temp;

   for (k = 0;  k < size -1; k++)
   {
      minindex = k;
      for (j = k+1; j < size; j++)
         if (tags[j] -> zip < tags[minindex] -> zip)
            minindex = j;
      temp = tags[k];
      tags[k] = tags[minindex];
      tags[minindex] = temp;
   }
}

void SelectTagSortName(Vector<who *> & tags, int size)
// precondition: tags contains pointers to size structs containing
//   data fields zip and name.
// postcondition: tags entries sorted so as to point to structs
//   in ordeer by name
{
   int k, j, minindex;
   who * temp;

   for (k = 0;  k < size -1; k++)
   {
      minindex = k;
      for (j = k+1; j < size; j++)
         if (tags[j] -> name < tags[minindex] -> name)
            minindex = j;
      temp = tags[k];
      tags[k] = tags[minindex];
      tags[minindex] = temp;
   }
}

int main()
{
   Vector<who *> tags(100);
   int size = 0;

   GetData(tags, size);
   cout << "From file:" << endl;
   ShowData(tags, size);

   SelectTagSortZip(tags, size);
   cout << "Sorted by zip:" << endl;
   ShowData(tags, size);

   SelectTagSortName(tags, size);
   cout << "Sorted by name:" << endl;
   ShowData(tags, size);
   
   return 0;
}

Sample output:

From file:
 Michael Ramm, 22301
 Nicholas Ramm, 22301
 Lenore Ramm, 27278
 Karl Ramm, 27701
 Barbara Ramm, 22301
 Eberhard Ramm, 37212
 Wolfhard Ramm, 22301
 Hartmut Ramm, 30582
 Mary-Kathlyn Ramm, 27278
 Dietolf Ramm, 27278
 Sieglind Ramm, 80802
 Ruth Ramm, 37355
 Dora Ramm, 27705
 Heinrich Ramm, 37355
Sorted by zip:
 Michael Ramm, 22301
 Nicholas Ramm, 22301
 Barbara Ramm, 22301
 Wolfhard Ramm, 22301
 Lenore Ramm, 27278
 Mary-Kathlyn Ramm, 27278
 Dietolf Ramm, 27278
 Karl Ramm, 27701
 Dora Ramm, 27705
 Hartmut Ramm, 30582
 Eberhard Ramm, 37212
 Ruth Ramm, 37355
 Heinrich Ramm, 37355
 Sieglind Ramm, 80802
Sorted by name:
 Barbara Ramm, 22301
 Dietolf Ramm, 27278
 Dora Ramm, 27705
 Eberhard Ramm, 37212
 Hartmut Ramm, 30582
 Heinrich Ramm, 37355
 Karl Ramm, 27701
 Lenore Ramm, 27278
 Mary-Kathlyn Ramm, 27278
 Michael Ramm, 22301
 Nicholas Ramm, 22301
 Ruth Ramm, 37355
 Sieglind Ramm, 80802
 Wolfhard Ramm, 22301