Structures in C++

There are various types of data type such as int, char float etc.

For example:


int  i;      here variable i can store only data of integer type
char c;   here variable c can store only data of character type
float  f; here variable f can store only data of floting-point type

Variable of each data type can store only single type of data.

But,  if we want to store different  type of data in a single variable then we use structure variable.

“structure” is user defined data type that allows to store data items of different data type.

  Defining a Structure

We can create a structure, by using the struct keyword.

The struct keyword defines a user defined new data type that can hold more than one member of different data type.

Format of structure is as follows –

struct structure_name 
{
   member definition;
   member definition;
   ...
   member definition;
} [one or more structure variables];

In a C programming Structures are used to represent a record.

Suppose you want to store the information of  a school student such as : −

  • Name
  • Class
  • Section
  • Roll Number

Example:  

struct Student 
{		char  name[50];
   		int  class;
   		char  section[100];
   		int  rollno;
} s1,s2;

Here s1 and s2 are the structure variable.

Another way of creating a structure variable is:

struct Student 
{		char  name[50];
   		int  class;
   		char  section[100];
   		int  rollno;
}
 int main()
{		 struct Student s1, s2;

return 0;
}

Example: Write a program to store and print the following information such as name, roll number, class and section of the student using structure.

#include 

using namespace std;

struct Student {
  char name[30];
  char section[1];
  int rollno;
  int Class;
}
s1;

int main() {
  cout << "Enter the name, rollno, class & section of  student";
  cin >> s1.name;
  cin >> s1.rollno;
  cin >> s1.Class;
  cin >> s1.section;

  cout << "\n  Student details";
  cout << "\n Name =" << s1.name;
  cout << "\n Rollno =" << s1.rollno;
  cout << "\n Class = " << s1.Class;
  cout << "\n Section = " << s1.section;

  return 0;
}

Output

Enter the name, rollno, class & section of student
Aditya				// enter by user
23456				// enter by user
12				// enter by user
A				// enter by user
 Student details
 Name = aditya
 Rollno = 23456
 Class = 12
 Section = A

Example: Write a program to store and print the following information such as name, roll number, class and section of 2 students using structure.

#include 

using namespace std;

struct Student {
  char name[30];
  char section[1];
  int rollno;
  int Class;
}
s1, s2;

int main() {
  cout << "Enter the name, rollno, class & section of 1st student";
  cin >> s1.name;
  cin >> s1.rollno;
  cin >> s1.Class;
  cin >> s1.section;

  cout << "Enter the name, rollno, class & section of 2nd  student";
  cin >> s2.name;
  cin >> s2.rollno;
  cin >> s2.Class;
  cin >> s2.section;

  cout << "\n 1st  Student details";
  cout << "\n Name =" << s1.name;
  cout << "\n Rollno =" << s1.rollno;
  cout << "\n Class = " << s1.Class;
  cout << "\n Section = " << s1.section;

  cout << "\n 2nd   Student details";
  cout << "\n Name =" << s2.name;
  cout << "\n Rollno =" << s2.rollno;
  cout << "\n Class = " << s2.Class;
  cout << "\n Section = " << s2.section;

  return 0;
}

Output

Enter the name, rollno, class & section of 1st  student
Aditya				// enter by user
23456				// enter by user
12				// enter by user
A				// enter by user
Enter the name, rollno, class & section of 2nd  student
Sam				// enter by user
23423				// enter by user
12				// enter by user
B		
1st  Student details
 Name = aditya
 Rollno = 23456
 Class = 12
 Section = A

2nd  Student details
 Name = Sam
 Rollno = 99999
 Class = 12
 Section = B
Categories C++