**Course Title:** Mastering Go: From Basics to Advanced Development **Section Title:** Control Structures and Functions **Topic:** Write Go programs that utilize control structures and functions.(Lab topic) **Objective:** In this lab, you will practice writing Go programs that utilize control structures and functions. You will apply the concepts learned in the previous topics to create robust and efficient programs. **Prerequisites:** Before starting this lab, make sure you have a good understanding of the following topics: * Conditional statements: if, else, switch * Loops: for, range * Creating and using functions: parameters, return values, and multiple returns * Understanding scope and visibility of variables **Lab Exercises:** ### Exercise 1: Implementing a Simple Calculator Create a Go program that takes in a mathematical operation (addition, subtraction, multiplication, division) and two numbers as input. Based on the operation, perform the corresponding calculation and print the result. ```go package main import "fmt" func calculate(num1 float64, num2 float64, operation string) float64 { switch operation { case "addition": return num1 + num2 case "subtraction": return num1 - num2 case "multiplication": return num1 * num2 case "division": if num2 != 0 { return num1 / num2 } else { return 0 } default: return 0 } } func main() { var num1 float64 var num2 float64 var operation string fmt.Print("Enter the first number: ") fmt.Scanln(&num1) fmt.Print("Enter the second number: ") fmt.Scanln(&num2) fmt.Print("Enter the operation (addition, subtraction, multiplication, division): ") fmt.Scanln(&operation) result := calculate(num1, num2, operation) fmt.Printf("The result is %.2f\n", result) } ``` **Exercise 2: Simulating a Bank Account** Create a Go program that simulates a bank account. The program should allow users to deposit and withdraw money, and display the current balance. ```go package main import "fmt" type BankAccount struct { balance float64 } func (acc *BankAccount) deposit(amount float64) { acc.balance += amount fmt.Printf("Deposited $%.2f. Current balance is $%.2f\n", amount, acc.balance) } func (acc *BankAccount) withdraw(amount float64) { if acc.balance >= amount { acc.balance -= amount fmt.Printf("Withdrawn $%.2f. Current balance is $%.2f\n", amount, acc.balance) } else { fmt.Println("Insufficient funds.") } } func (acc *BankAccount) displayBalance() { fmt.Printf("Current balance is $%.2f\n", acc.balance) } func main() { var acc BankAccount for { fmt.Println("\n1. Deposit") fmt.Println("2. Withdraw") fmt.Println("3. Display Balance") fmt.Println("4. Exit") var choice int fmt.Scanln(&choice) switch choice { case 1: var amount float64 fmt.Print("Enter amount to deposit: ") fmt.Scanln(&amount) acc.deposit(amount) case 2: var amount float64 fmt.Print("Enter amount to withdraw: ") fmt.Scanln(&amount) acc.withdraw(amount) case 3: acc.displayBalance() case 4: return default: fmt.Println("Invalid choice.") } } } ``` **Key Concepts:** * Control structures (if-else statements, switch statements, loops) are essential in controlling the flow of a program. * Functions allow for code reusability and make programs more modular. * Scope and visibility of variables determine where and when variables can be accessed. **Practical Takeaways:** * Practice using control structures and functions in Go programs. * Use switch statements when dealing with multiple conditions. * Use functions to perform specific tasks and avoid code duplication. **Additional Resources:** For more information on control structures and functions in Go, refer to the official Go documentation: [https://tour.golang.org](https://tour.golang.org) **Leave a comment/ask for help:** If you have any questions or need help with the lab exercises, please leave a comment below. **What's Next:** In the next topic, we will cover understanding arrays and their properties. Stay tuned! **Working with Data Structures: Arrays, Slices, and Maps**