C++ Tutorial/Structure/structure pointer

Compare address

<source lang="cpp">#include <ios>

1. include <iostream>
2. include <ostream>

struct MyStruct {

 int x;
 int y;

}; int main() {

 MyStruct demo[10];
 std::cout << std::boolalpha;
 std::cout << (&demo[0]   < &demo[2])   << "\n";
 std::cout << (&demo[0]   == demo)      << "\n";
 std::cout << (&demo[10]  > &demo[9])   << "\n";
 std::cout << (&demo[0].x < &demo[0].y) << "\n";

}</source>

true
true
true
true

Define pointer for structure

<source lang="cpp">#include <iostream> using namespace std; struct MyStructure {

  int n;
  float f;
  float f2;

}; int main() {

MyStructure myMyStructure;
MyStructure *ptrMyStructure;
//set the f of the structure
myMyStructure.f = 1000;
//intialize the pointer
ptrMyStructure = &myMyStructure;
//change the pointers f
ptrMyStructure->f = 2000;
//print out the structures f
cout << myMyStructure.f << "\n";
return 0;

}</source>

2000

Pointers to structures

<source lang="cpp">#include <iostream.h>

1. include <stdlib.h>

struct Employee {

 char title [50];
 int year;

};

int main () {

 char buffer[50];
 Employee aEmployee;
 Employee * pEmployee;
 pEmployee = & aEmployee;
 cout << "Enter title: ";
 cin.getline (pEmployee->title,50);
 cout << "Enter year: ";
 cin.getline (buffer,50);
 pEmployee->year = atoi (buffer);
 cout << "\nYou have entered:\n";
 cout << pEmployee->title;
 cout << " (" << pEmployee->year << ")\n";
 return 0;

}</source>

Enter title: Enter year:
You have entered:
 (^CTerminate batch job (Y/N)? n

Use -> for structure pointer

<source lang="cpp">#include <iostream> using namespace std; struct account {

  int accountnum;
  float balance;
  float interestrate;

}; int main() {

account myaccount;
account *ptraccount;
ptraccount->balance = 1000;
      return 0;

}</source>