Explain the concept of an array within a structure in C programming

An array of structure in C programming is a collection of different datatype variables, grouped together under a single name.

General form of structure declaration

The structural declaration is as follows −

struct tagname{
   datatype member1;
   datatype member2;
   datatype member n;
};

Here, struct is the keyword.

tagname specifies the name of structure.

member1, member2 specifies the data items that make up structure.

Example

The following example shows the usage of array within a structure in C programming −

struct book{
   int pages;
   char author [30];
   float price;
};

Example

Following is the C program to demonstrate the use of an array within a structure −

#include <stdio.h>
// Declaration of the structure candidate
struct candidate {
   int roll_no;
   char grade;
   // Array within the structure
   float marks[4];
};
// Function to displays the content of
// the structure variables
void display(struct candidate a1){
   printf("Roll number : %d\n", a1.roll_no);
   printf("Grade : %c\n", a1.grade);
   printf("Marks secured:\n");
   int i;
   int len = sizeof(a1.marks) / sizeof(float);
   // Accessing the contents of the
   // array within the structure
   for (i = 0; i < len; i++) {
      printf("Subject %d : %.2f\n",
      i + 1, a1.marks[i]);
   }
}
// Driver Code
int main(){
   // Initialize a structure
   struct candidate A= { 1, 'A', { 98.5, 77, 89, 78.5 } };
   // Function to display structure
   display(A);
   return 0;
}

Output

When the above program is executed, it produces the following result −

Roll number : 1
Grade : A
Marks secured:
Subject 1 : 98.50
Subject 2 : 77.00
Subject 3 : 89.00
Subject 4 : 78.50