Structure

1. "Define a structure of student having data member’s name, address, marks in C language, and marks in information system. Take data for n students in an array dynamically and find the total marks obtained."
   
   #include <stdio.h>

   #include <string.h>

   
   

   // Define the structure for a student

   struct Student {

       char name[50];

       char address[100];

       int marks;

   };

   
   

   int main() {

       // Declare a student variable

       struct Student student1;

   
   

       // Assign values to the student1 fields

       strcpy(student1.name, "Suman Adhikari");

       strcpy(student1.address, "Kathmandu, Nepal");

       student1.marks = 85;

   
   

       // Print the student details

       printf("Name: %s\n", student1.name);

       printf("Address: %s\n", student1.address);

       printf("Marks: %d\n", student1.marks);

   
   

       return 0;

   }

   
   

   
   
   
   
   
2. define structure of employee having data members name, address, age, and salary. Take data for n employee in an array dynamically and find the average salary."
   
   #include <stdio.h>

   #include <stdlib.h>

   
   

   // Define the Employee structure

   struct Employee {

       char name[100];

       char address[100];

       int age;

       float salary;

   };

   
   

   int main() {

       int n;

       float sumSalary = 0.0, avgSalary;

   
   

       // Input the number of employees

       printf("Enter the number of employees: ");

       scanf("%d", &n);

   
   

       // Dynamically allocate memory for n employees

       struct Employee *employees = (struct Employee *)malloc(n * sizeof(struct Employee));

   
   

       // Check if memory has been allocated successfully

       if (employees == NULL) {

           printf("Memory allocation failed.\n");

           return 1;

       }

   
   

       // Input data for each employee

       for (int i = 0; i < n; i++) {

           printf("Enter details for employee %d:\n", i + 1);

   
   

           printf("Name: ");

           scanf(" %[^\n]%*c", employees[i].name); // to read string with spaces

   
   

           printf("Address: ");

           scanf(" %[^\n]%*c", employees[i].address);

   
   

           printf("Age: ");

           scanf("%d", &employees[i].age);

   
   

           printf("Salary: ");

           scanf("%f", &employees[i].salary);

   
   

           // Add salary to sum

           sumSalary += employees[i].salary;

       }

   
   

       // Calculate the average salary

       avgSalary = sumSalary / n;

   
   

       // Output the average salary

       printf("The average salary is: %.2f\n", avgSalary);

   
   

       // Free the allocated memory

       free(employees);

   
   

       return 0;

   }

   
   
   
   
   
   
   
   
   
3. "Write a program to enter two 3x3 matrices and calculate the product of given matrices."
   
   #include <stdio.h>

   
   

   #define SIZE 3

   
   

   // Define a struct for a 3x3 matrix

   struct Matrix {

       int data[SIZE][SIZE];

   };

   
   

   // Function prototypes

   void inputMatrix(struct Matrix *matrix, const char *name);

   void printMatrix(struct Matrix *matrix);

   void multiplyMatrices(struct Matrix *matrix1, struct Matrix *matrix2, struct Matrix *result);

   
   

   int main() {

       struct Matrix matrix1, matrix2, result;

   
   

       // Input matrices

       inputMatrix(&matrix1, "Matrix 1");

       inputMatrix(&matrix2, "Matrix 2");

   
   

       // Multiply matrices

       multiplyMatrices(&matrix1, &matrix2, &result);

   
   

       // Output the result matrix

       printf("Resultant matrix after multiplication:\n");

       printMatrix(&result);

   
   

       return 0;

   }

   
   

   // Function to input a matrix

   void inputMatrix(struct Matrix *matrix, const char *name) {

       printf("Enter elements of %s (3x3):\n", name);

       for (int i = 0; i < SIZE; i++) {

           for (int j = 0; j < SIZE; j++) {

               scanf("%d", &matrix->data[i][j]);

           }

       }

   }

   
   

   // Function to print a matrix

   void printMatrix(struct Matrix *matrix) {

       for (int i = 0; i < SIZE; i++) {

           for (int j = 0; j < SIZE; j++) {

               printf("%d ", matrix->data[i][j]);

           }

           printf("\n");

       }

   }

   
   

   // Function to multiply two matrices

   void multiplyMatrices(struct Matrix *matrix1, struct Matrix *matrix2, struct Matrix *result) {

       for (int i = 0; i < SIZE; i++) {

           for (int j = 0; j < SIZE; j++) {

               result->data[i][j] = 0;

               for (int k = 0; k < SIZE; k++) {

                   result->data[i][j] += matrix1->data[i][k] * matrix2->data[k][j];

               }

           }

       }

   }