Medium_ExampleCode.ts

interface CalculatorInterface {
  add(a: number, b: number): number;
  subtract(a: number, b: number): number;
  divide(a: number, b: number): number;
  isEnabled: boolean;
}

class RealCalculator implements CalculatorInterface {
  add(a: number, b: number) { return a + b; }
  subtract(a: number, b: number) { return a - b; }
  divide(a: number, b: number) { return a / b; }
  get isEnabled() { return true; }
}