Trust Coding : Programming: 🧵 Array & Nested Structures in C

🧵 Array of Structures and Nested Structures in C

Structures in C allow grouping different data types into a single unit. When we use arrays with structures or place one structure inside another, we can model real-world data more effectively.

🔹 Array of Structures

We use an array of structures when we want to store multiple records of the same type.

✅ Example: Store information of 3 students

#include <stdio.h>

struct Student {
    int id;
    char name[50];
    float marks;
};

int main() {
    struct Student students[3];

    for (int i = 0; i < 3; i++) {
        printf("Enter info for student %d:\n", i + 1);
        printf("ID: ");
        scanf("%d", &students[i].id);
        printf("Name: ");
        scanf(" %[^\n]", students[i].name);
        printf("Marks: ");
        scanf("%f", &students[i].marks);
    }

    printf("\nStudent Records:\n");
    for (int i = 0; i < 3; i++) {
        printf("ID: %d, Name: %s, Marks: %.2f\n", 
            students[i].id, students[i].name, students[i].marks);
    }

    return 0;
}

Note: Use students[i].field to access each member of the structure.

🔹 Nested Structures

A nested structure is a structure within another structure. It helps represent grouped sub-details (like address inside employee data).

✅ Example: Employee with Address

#include <stdio.h>

struct Address {
    char city[30];
    char state[30];
    int zip;
};

struct Employee {
    int id;
    char name[50];
    struct Address address;
};

int main() {
    struct Employee emp;

    printf("Enter Employee ID: ");
    scanf("%d", &emp.id);
    printf("Enter Name: ");
    scanf(" %[^\n]", emp.name);
    printf("Enter City: ");
    scanf(" %[^\n]", emp.address.city);
    printf("Enter State: ");
    scanf(" %[^\n]", emp.address.state);
    printf("Enter ZIP Code: ");
    scanf("%d", &emp.address.zip);

    printf("\nEmployee Information:\n");
    printf("ID: %d\n", emp.id);
    printf("Name: %s\n", emp.name);
    printf("City: %s, State: %s, ZIP: %d\n",
           emp.address.city, emp.address.state, emp.address.zip);

    return 0;
}

Note: Access nested fields using emp.address.city, emp.address.zip, etc.

🔚 Summary Table

Concept	Syntax Example	Use Case
Array of Structures	`struct Student students[100];`	To manage a list of similar records
Nested Structures	`struct Employee { struct Address a; }`	To represent complex or grouped sub-data

Trust Coding : Programming

🧵 Array & Nested Structures in C