Bot program to count the products bought in the supermarket, with total sum.

package main

import (
    "fmt"
    "strconv"
)

func main() {
    var userInput string
    sum := 0
    for {
        fmt.Print("Enter a number or 'X' to quit: ")
        fmt.Scan(&userInput)
        if userInput == "X" {
            fmt.Printf("Sum: %d", sum)
            break
        }
        value, err := strconv.Atoi(userInput)
        if err != nil {
            fmt.Println("Bad value!")
            continue
        }
        sum += value
    }
}