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Initialize a struct in accordance with C programming language

In this tutorial, we will learn about how to create and initialize a struct in c programming language?
Submitted by Shubh Pachori, on July 11, 2022

A struct is a keyword that creates a user-defined datatype in the C programming language. A struct keyword creates datatypes that can be used to group items of possibly different types and same types into a single datatype.

For example, if an administration wants to create a file for their students to handle their information they can construct a structure by using the struct keyword because as we know that a student's name is a character value and its roll number and marks are integer values. Hence, it is a problem to store them in the same datatype, but the struct allows you to do the same using it.

Syntax to construct a structure using struct keyword

struct Student{
    int roll_no;
    char name[30];
};

Here, the struct is a keyword, Student is a tag name, roll_no and name are its members.

Using the struct keyword, we can create a workspace for any heterogeneous and homogeneous type of data to store and manipulate at a single place.

Here, we are using designated initializer to initialize a structure.

C language code to understand how we can initialize a structure?

#include <stdio.h>

// Creating a Student named structure
typedef struct Student {
    // name and roll_no are its member
    char name[20];
    int rollno;
} Student;

int main()
{
    // Declaring two Student type variables
    Student s1, s2;

    // Initializing 1st Student
    s1 = (Student){.name = "shubh", .rollno = 1 };
    // Initializing 2nd  Student
    s2 = (Student){.name = "pachori", .rollno = 2 };

    printf("\n%d %s\n", s1.rollno, s1.name);
    printf("\n%d %s\n", s2.rollno, s2.name);

    return 0;
}

Output:

1 shubh

2 pachori

But if we want to input values by the keyboard then we have to use a different method for it.

Here is an example of how we can input values in a structure using a keyboard go through with the below code.

#include <stdio.h>

// Creating a Student named structure
typedef struct Student {
    // name and roll_no are its member
    char name[20];
    int rollno;
} Student;

int main()
{
    // Declaring two Student type variables
    Student s1, s2;

    // Data input through keyboard of s1
    printf("Enter Roll Number First Student: ");
    scanf("%d", &s1.rollno);
    printf("Enter Name First Student: ");
    scanf("%s", s1.name);

    // Data input through keyboard of s2
    printf("Enter Roll Number Second Student: ");
    scanf("%d", &s2.rollno);
    printf("Enter Name Second Student: ");
    scanf("%s", s2.name);

    printf("\n%d %s\n", s1.rollno, s1.name);
    printf("\n%d %s\n", s2.rollno, s2.name);

    return 0;
}

Output:

Enter Roll Number First Student: 101
Enter Name First Student: Subh
Enter Roll Number Second Student: 102
Enter Name Second Student: Pranit

101 Subh

102 Pranit