Write your first Go program

Write your first Go program:

In this tutorial, we will learn how to write a basic go program. This program will take one String as input from the user and print it back.

For Go programs, we need to write it in a file with extension .go. You can create a file with any name and run it.

Write a Go program:

Let’s create a file example.go and write the below code:

package main

import "fmt"

func main() {
	fmt.Println("Hello World !!")
}

Here,

• main is the package of this program. We can have multiple files with the same package and each folder can have maximum of one package.
• import is used to import another package in a package. Here, we are importing fmt package, which is a go package. We will use this package to read text from the user and to print that text on console.
• fmt.Println is used to print something on console. We can pass one string to this method and it prints that value.
• main method is the entry point. It will first run the lines in this method.

Run the Go program:

To run the program, we can use go run command. Open a terminal, move to the folder that has this file and run the below command:

go run example.go

How to get user input:

The fmt modules provides methods to take a string as input from the user and put that in a variable. Using Println, we can print that variable back.

package main

import "fmt"

func main() {
	var num int

	fmt.Println("Enter a number: ")
	fmt.Scanln(&num)

	fmt.Println(num)
}

Here,

• We are using Scanln to read the user input value, i.e. a number.
• It reads the number and stores it in num
• The last Println statement prints the value of num.

It will print output as like below:

Enter a number: 
12
12