PairOfShoes.scala

class PairOfShoes(var leftSize: Int, var rightSize: Int) {
    def mix(newLeftSize: Int, newRightSize: Int) =
      {
        leftSize = newLeftSize
        rightSize = newRightSize
      }

    override def hashCode(): Int = leftSize + 31 * rightSize

    def canEqual(that: Any): Boolean = that match {
      case p: PairOfShoes => true
      case _ => false
    }

    override def equals(that: Any): Boolean = {
      def strictEquals(that: PairOfShoes) =
        {
          this.leftSize == that.leftSize && this.rightSize == that.rightSize
        }
      that match {
        case a: AnyRef if this eq  a => true
        case p: PairOfShoes => (p canEqual this) && strictEquals(p)
        case _ => false
      }
    }