Introduction

A countdown timer is a useful tool for various scenarios such as tracking time during an activity or setting reminders.
This program demonstrates how to create a countdown timer in Go that counts down from a given number of seconds to zero.

Objective

The objective of this project is to create a simple console-based countdown timer that takes input in seconds and displays the countdown in real time.
This helps learners understand Go’s time-related functions and loops.

Code

package main

import (
	"fmt"
	"time"
)

func main() {
	var seconds int
	fmt.Println("Welcome to the Countdown Timer!")
	fmt.Print("Enter the number of seconds for the countdown: ")
	fmt.Scanln(&seconds)

	if seconds <= 0 {
		fmt.Println("Please enter a positive number of seconds.")
		return
	}

	fmt.Println("Countdown starts now:")
	for i := seconds; i > 0; i-- {
		fmt.Printf("%d seconds remaining...\n", i)
		time.Sleep(1 * time.Second)
	}

	fmt.Println("Time's up!")
}

            

Explanation

The program structure is as follows:

• User Input: The program prompts the user to enter the number of seconds for the countdown.
• Validation: The input is validated to ensure it’s a positive number.
• Countdown Loop: A for loop iterates from the given number down to 1, printing the remaining seconds and pausing for 1 second between iterations using time.Sleep.
• Completion Message: Once the countdown reaches zero, the program prints “Time’s up!” to indicate the end of the countdown.

How to Run the Program

1. Ensure you have Go installed on your system. You can download it from
   Go’s official website.
2. Save the code in a file named countdown_timer.go.
3. Open a terminal and navigate to the directory containing the file.
4. Run the program with the following command:

   go run countdown_timer.go

5. Enter the desired countdown duration in seconds and watch the countdown in real time.