**Course Title:** Mastering C: From Fundamentals to Advanced Programming **Section Title:** Control Structures and Functions **Topic:** Write C programs that use control structures and functions to solve problems.(Lab topic) **Introduction** In the previous topics, we covered the basics of C programming, including variables, data types, operators, control structures, and functions. Now, it's time to put these concepts into practice by writing C programs that use control structures and functions to solve real-world problems. This lab topic will help you apply the theoretical knowledge to practical problems, making you more proficient in C programming. **Problem 1: Calculating the Area and Perimeter of a Rectangle** Write a C program that calculates the area and perimeter of a rectangle given its length and width. The program should use a function to calculate the area and another function to calculate the perimeter. **Example Code** ```c #include <stdio.h> // Function to calculate the area of a rectangle int calculateArea(int length, int width) { return length * width; } // Function to calculate the perimeter of a rectangle int calculatePerimeter(int length, int width) { return 2 * (length + width); } int main() { int length, width, area, perimeter; // Get the length and width of the rectangle from the user printf("Enter the length of the rectangle: "); scanf("%d", &length); printf("Enter the width of the rectangle: "); scanf("%d", &width); // Calculate the area and perimeter using functions area = calculateArea(length, width); perimeter = calculatePerimeter(length, width); // Display the results printf("Area of the rectangle: %d\n", area); printf("Perimeter of the rectangle: %d\n", perimeter); return 0; } ``` **Explanation** * We define two functions: `calculateArea` and `calculatePerimeter`. These functions take the length and width of the rectangle as arguments and return the calculated area and perimeter, respectively. * In the `main` function, we prompt the user to enter the length and width of the rectangle. * We call the `calculateArea` and `calculatePerimeter` functions with the user-provided length and width, storing the results in `area` and `perimeter` variables. * Finally, we display the calculated area and perimeter to the user. **Problem 2: Finding the Maximum and Minimum of Three Numbers** Write a C program that finds the maximum and minimum of three numbers using functions. **Example Code** ```c #include <stdio.h> // Function to find the maximum of three numbers int findMax(int num1, int num2, int num3) { if (num1 > num2 && num1 > num3) { return num1; } else if (num2 > num1 && num2 > num3) { return num2; } else { return num3; } } // Function to find the minimum of three numbers int findMin(int num1, int num2, int num3) { if (num1 < num2 && num1 < num3) { return num1; } else if (num2 < num1 && num2 < num3) { return num2; } else { return num3; } } int main() { int num1, num2, num3, max, min; // Get three numbers from the user printf("Enter the first number: "); scanf("%d", &num1); printf("Enter the second number: "); scanf("%d", &num2); printf("Enter the third number: "); scanf("%d", &num3); // Find the maximum and minimum using functions max = findMax(num1, num2, num3); min = findMin(num1, num2, num3); // Display the results printf("Maximum of the three numbers: %d\n", max); printf("Minimum of the three numbers: %d\n", min); return 0; } ``` **Explanation** * We define two functions: `findMax` and `findMin`. These functions take three numbers as arguments and return the maximum and minimum values, respectively. * In the `main` function, we prompt the user to enter three numbers. * We call the `findMax` and `findMin` functions with the user-provided numbers, storing the results in `max` and `min` variables. * Finally, we display the maximum and minimum values to the user. **Key Concepts** * Control structures (if-else, switch) and functions can be combined to solve real-world problems. * Functions can be used to modularize code and improve readability. * Programs can be designed to solve specific problems by applying theoretical concepts. **Practice** * Write a C program that calculates the sum of all even numbers in a given range using a function. * Write a C program that finds the factorial of a number using a recursive function. **Additional Resources** * [C Programming Tutorial by tutorialspoint](https://www.tutorialspoint.com/cprogramming/index.htm) * [C Programming Language by Dennis Ritchie](https://www.dummies.com/programming/c/c-programming-language/) **What's Next?** In the next topic, we will discuss declaring and initializing arrays, including single-dimensional, multi-dimensional, and dynamic arrays. Do you have any questions or need help with any of the topics covered in this lab? Please leave a comment below.