03. HEX

class Hex {
  constructor(value) {
    this.value = Number(value);
  }

  valueOf() {
    return this.value;
  }

  toString() {
    return `0x${this.value.toString(16).toUpperCase()}`;
  }

  plus(arg) {
    if (arg instanceof Hex) {
      return new Hex(this.value + arg.valueOf());
    }
    return new Hex(this.value + Number(arg));
  }

  minus(arg) {
    if (arg instanceof Hex) {
      return new Hex(this.value - arg.valueOf());
    }
    return new Hex(this.value - Number(arg));
  }

  parse(hex) {
    return parseInt(`${hex}`, 16);
  }
}