Welcome to your first Swift programming experience! In this section, we will guide you through writing, understanding, and running your first Swift program. By the end of this lesson, you will have a basic understanding of Swift's syntax and structure.

• Write a simple Swift program.
• Understand the basic structure of a Swift program.
• Learn how to run a Swift program.

Let's start with a simple "Hello, World!" program. This is a traditional first program that prints "Hello, World!" to the console.

1. Open Xcode: If you haven't installed Xcode yet, please refer to the previous section on setting up the development environment.

2. Create a New Playground:

   • Open Xcode.
   • Select "File" > "New" > "Playground".
   • Choose a template (select "Blank").
   • Name your playground (e.g., "HelloWorld") and save it to a convenient location.

3. Write the Code:

   • In the playground, you will see a text editor. Type the following code:

• import Foundation: This line imports the Foundation framework, which provides essential data types, collections, and operating-system services to define the base layer of functionality for your app. For this simple program, it's not strictly necessary, but it's good practice to include it.
• print("Hello, World!"): This line prints the string "Hello, World!" to the console. The print function is used to output text or other information to the console.

• To run the program, simply click the "Run" button (a triangle icon) in the lower left corner of the playground window.
• You should see the output "Hello, World!" in the console area at the bottom of the playground.

Let's expand our program to include a simple arithmetic operation and print the result.

• let greeting = "Hello, World!": This line declares a constant named greeting and assigns it the value "Hello, World!".
• print(greeting): This line prints the value of the greeting constant.
• let a = 5: This line declares a constant named a and assigns it the value 5.
• let b = 10: This line declares a constant named b and assigns it the value 10.
• let sum = a + b: This line declares a constant named sum and assigns it the result of adding a and b.
• print("The sum of \\(a) and \\(b) is \\(sum)"): This line prints a string that includes the values of a, b, and sum. The \\() syntax is used for string interpolation, allowing you to insert the values of variables into a string.

• Click the "Run" button again to execute the expanded program.
• You should see the following output in the console:

Modify the program to print a personalized greeting. Change the value of the greeting constant to include your name.

Solution:

Modify the program to perform a multiplication operation instead of addition. Print the result.

Solution:

• Syntax Errors: Ensure that you use the correct syntax, such as matching parentheses and quotation marks.
• Variable Naming: Use meaningful variable names to make your code more readable.
• String Interpolation: Remember to use \\() for inserting variable values into strings.

Congratulations! You've written and run your first Swift program. You now understand the basic structure of a Swift program and how to use the print function to output text to the console. In the next section, we will dive deeper into Swift's basic syntax and structure. Keep practicing and experimenting with the code to reinforce your learning.