Zeiger auf Strukturen

dynamic_array.cpp

//	Dynamic array of type student
 
#include <iostream>
using namespace std;
 
int main()
{
 struct Student
  {
    long long int matrikel;
              int skz;
              char name[30], vorname[20];
  };
 
 int     i, n;
 Student *gruppe, *pg;        // pointer at Student
 
 cout << endl;
 cout << " How many Students : "; 
 cin >> n;		// input n
 
 gruppe = new Student[n]; // allocate memory
 
 for (i = 0; i < n; i++)
  {
    cout << endl << "Student nr. " << i << endl;
    cout << "Familenname : ";
    cin  >> gruppe[i].name;
    cout << "Vorname     : ";
    cin  >> (gruppe+i)->vorname;  
    cout << "Matrikelnummer : ";
    cin  >> gruppe[i].matrikel;
    cout << "SKZ            : ";
    cin  >> gruppe[i].skz;
  }
 cout << endl;
 
 i = 3;
 if ( i < n)
 {
   cout << endl;
   cout << "Student nr. " << i << " : ";
   cout << gruppe[i].vorname << " " << gruppe[i].name << " , ";
   cout << gruppe[i].matrikel << " , " << gruppe[i].skz << endl;
 
//		Let us have a look on equivalent data acesses
   pg = gruppe+i;
   cout << endl << "  Test" << endl;
 
//		Access on string 
   cout << pg->vorname      << " " 
        << (*pg).vorname    << endl;
 
//		Acess on first string character
   cout << pg->vorname[0]   << " " 
        << *pg->vorname     << " " 
	<< *(*pg).vorname   << " " 
	<< (*pg).vorname[0] << endl;
 
//		Acess on fourth string character
   cout << pg->vorname[3]       << " " 
        << *(pg->vorname+3)     << " " 
	<< *((*pg).vorname+3)   << " " 
	<< (*pg).vorname[3]     << endl; }
 
 delete [] gruppe;           // deallocate memory
 
 system("PAUSE");
 return EXIT_SUCCESS; 
}

Testdaten:

input.txt

4
Lennon
John
6255308
810
McCartney
Paul
6255221
406
Harrison
George
6155003
860
Starr
Ringo
6355985
412