Go Program to Add Two Numbers

1. Introduction

When learning a new programming language, one of the first tasks often undertaken is writing a program to add two numbers. It's a simple yet effective way to familiarize oneself with a language's syntax and structure. In this post, we'll cover how to write a program in Go (or Golang, as it's commonly known) to perform this basic arithmetic operation.

2. Program Overview

The primary objective of our program will be to:

1. Prompt the user to input two numbers.

2. Calculate the sum of the provided numbers.

3. Display the resultant sum to the user.

3. Code Program

// Start by declaring the main package, the entry point for our application.
package main

// Import the fmt package, essential for formatted I/O operations.
import "fmt"

// Define the main function which will be executed when the program runs.
func main() {
    // Declare three variables of type float64 to store the two numbers and their sum.
    var num1, num2, sum float64

    // Prompt the user for the first number and read it into the num1 variable.
    fmt.Print("Enter the first number: ")
    fmt.Scan(&num1)

    // Repeat the process for the second number, storing it in the num2 variable.
    fmt.Print("Enter the second number: ")
    fmt.Scan(&num2)

    // Compute the sum of the two numbers.
    sum = num1 + num2

    // Display the result to the user using formatted printing.
    fmt.Printf("The sum of %v and %v is: %v\n", num1, num2, sum)
}

Output:

Enter the first number: 10
Enter the second number: 20
The sum of 10 and 20 is: 30

4. Step By Step Explanation

1. Package and Import Declarations: We begin with the package main, which indicates our program's entry point. The fmt package is imported next, giving us access to input-output functions.

// Start by declaring the main package, the entry point for our application.
package main

// Import the fmt package, essential for formatted I/O operations.
import "fmt"

2. Variable Declaration: Using the var keyword, we declare three variables of type float64 to store our numbers and their sum.

    // Declare three variables of type float64 to store the two numbers and their sum.
    var num1, num2, sum float64

3. User Input: fmt.Print provides a prompt for the user, while fmt.Scan reads the user's input, storing it in the specified variable.

    // Prompt the user for the first number and read it into the num1 variable.
    fmt.Print("Enter the first number: ")
    fmt.Scan(&num1)

    // Repeat the process for the second number, storing it in the num2 variable.
    fmt.Print("Enter the second number: ")
    fmt.Scan(&num2)

4. Summation: We then add num1 and num2, storing the result in the sum variable.

    // Compute the sum of the two numbers.
    sum = num1 + num2

5. Displaying the Result: Lastly, fmt.Printf is used to format and display the summation result to the user.

    // Display the result to the user using formatted printing.
    fmt.Printf("The sum of %v and %v is: %v\n", num1, num2, sum)