06. Cake

package main

import (
    "fmt"
    "strconv"
)

func main() {
    var x, y, eatenPieces int
    fmt.Scanln(&x)
    fmt.Scanln(&y)

    var cakePieces = x * y

    var input string
    fmt.Scanln(&input)

    for cakePieces > 0 && input != "STOP" {
        eatenPieces,_ = strconv.Atoi(input)
        cakePieces -= eatenPieces
        fmt.Scanln(&input)
    }

    if cakePieces >= 0 {
        fmt.Printf("%d pieces are left.\n", cakePieces)
    } else {
        fmt.Printf("No more cake left! You need %d pieces more.\n", cakePieces * -1)
    }
}