user input/output

The fmt package in Go provides a variety of functions for formatting and printing text. It is a standard library package, so you can use it without installing any additional dependencies.

Here are some examples of how you might use the fmt package:

package main

import "fmt"

func main() {
    // Print a string to the console
    fmt.Println("Hello, World!")

    // Print an integer value
    fmt.Println(42)

    // Print a floating point value with a specific number of decimal places
    fmt.Printf("%.2f", 3.1415926535)

    // Print a value with a specific width and precision
    fmt.Printf("%10.2f", 3.1415926535)
}

Some of the functions provided by the fmt package include:

Printf: This function formats and prints values to the console using a format string. Sprintf: This function formats and returns a string instead of printing to the console. Fprintf: This function formats and prints values to a specified io.Writer interface. Scanf: This function reads values from the console and stores them in variables using a format string. Fscanf: This function reads values from a specified io.Reader interface and stores them in variables using a format string.

Examples of using these functions:

Printf:

fmt.Printf("Hello, %s! You are %d years old.\n", name, age)

Sprintf:

message := fmt.Sprintf("Hello, %s! You are %d years old.\n", name, age)

Fprintf:

f, err := os.Create("output.txt")
if err != nil {
panic(err)
}
defer f.Close()
fmt.Fprintf(f, "Hello, %s! You are %d years old.\n", name, age)

Scanf:

fmt.Print("Enter your name: ")
var name string
fmt.Scanf("%s", &name)

Fscanf:

f, err := os.Open("input.txt")
if err != nil {
panic(err)
}
defer f.Close()
var name string
fmt.Fscanf(f, "%s", &name)

For more information, you can refer to the documentation for the fmt package

In Go, input is typically taken from the standard input stream (stdin) using the fmt package's Scan function. The input is then stored in a variable for further processing.

For example:
```go
package main

import (
"fmt"
)

func main() {
var input string
fmt.Scan(&input) // reads input from stdin and stores it in the variable "input"
fmt.Println("You entered:", input)
}

Output is typically done using the fmt package's Print or Println functions, which write to the standard output stream (stdout).

For example:

package main

import (
"fmt"
)

func main() {
fmt.Println("This is the output")
}