Semigroups3.scala

// add any two integer value
def addInt(a: Int, b: Int): Int = a + b

// add employe salary to their account balances
def addMoneyMap(balances: Map[String, Money], salary: Map[String, Money]): Map[String, Money] = {
  balances.foldLeft(salaries){
    case (acc, (name, money)) =>
      acc + (name -> acc.get(name).map(addMoney(_ , money)).getOrElse(money))
  }
}