//
// program to count out change:
//
// prompt user for number of cents.
// print equivalent number of dollars, quarters, dimes, nickels, pennies.
//
// this version uses a "var" variable
// and includes some use of conditional execution:
//   rejects amounts < 0
//   only prints nonzero amounts
//
//

// the next line is needed to avoid warnings with the newest Scala
// "comment it out" (insert a //) if you compile with an earlier version
import scala.io.StdIn._

println("number of cents?")

val cents = readInt
println("input "+cents)

if (cents < 0) {
  println("number must be at least 0")
  sys.exit(0)
}

var centsLeft = cents

val dollars = cents / 100
if (dollars > 0) {
  println(dollars + " dollars")
  centsLeft = centsLeft - dollars*100
}

val quarters = centsLeft / 25
if (quarters > 0) {
  println(quarters + " quarters")
  centsLeft = centsLeft - quarters*25
}

val dimes = centsLeft / 10
if (dimes > 0) {
  println(dimes + " dimes")
  centsLeft = centsLeft - dimes*10
}

val nickels = centsLeft / 5
if (nickels > 0) {
  println(nickels + " nickels")
  centsLeft = centsLeft - nickels*5
}

val pennies = centsLeft
if (pennies > 0) {
  println(pennies + " pennies")
}
val checkAnswer = dollars*100 + quarters*25 + dimes*10 + nickels*5 + pennies
// println("that adds up to "+checkAnswer)

if (checkAnswer == cents) {
  println("answer checks out!")
}
else {
  println("wrong answer!  " +checkAnswer)
}

// println("in dollars and cents "+dollars+"."+(cents%100))