Go Program to Check if a Number Is Even or Odd

1. Introduction

Determining if a number is even or odd is a basic computational task and an introduction to conditional structures in programming. In this article, we'll take a closer look at how to create a program in Golang that evaluates the parity of a number given by the user.

2. Program Overview

The primary objectives of our Go program are to:

1. Prompt the user to provide a number.

2. Evaluate if the entered number is even or odd.

3. Display the assessment to the user.

3. Code Program

// The entry point of our application is denoted by the main package declaration.
package main

// The fmt package is harnessed for managing input and output operations.
import "fmt"

// Execution of our program begins with the main function.
func main() {
    // We declare an int variable to store the user's input.
    var number int

    // The user is requested to input a number, which is then stored in the number variable.
    fmt.Print("Enter a number: ")
    fmt.Scan(&number)

    // A conditional statement checks the remainder when the number is divided by 2.
    if number % 2 == 0 {
        fmt.Println("The number is even.")
    } else {
        fmt.Println("The number is odd.")
    }
}

Output:

If the user enters the number 5, the program's output will be:
The number is odd.

However, if the user provides 4 as input, the display would read:
The number is even.

4. Step By Step Explanation

1. Package and Import Directives: We start with the package main to signify our program's initiation point. For handling inputs and outputs, the fmt package is integrated.

2. Variable Declaration: Using the var keyword, an integer variable named number is initialized to store the number provided by the user.

3. Receiving User Input: With fmt.Print, we provide a prompt to the user, and with fmt.Scan, the user's input is stored in the number variable.

4. Even-Odd Evaluation: To determine the number's parity, the remainder of the number when divided by 2 is checked. If the remainder is 0, the number is even; otherwise, it's odd.

5. Displaying the Result: Based on the evaluation, an appropriate message is printed, informing the user whether the number is even or odd.