(∣x−xi∣+∣y−yi∣)(|x-x_{i}| + |y-y_{i}|)(∣x−xi∣+∣y−yi∣) 翻译成了 (∣x−xi∣,∣y−yi∣)(|x-x_{i}|,|y-y_{i}|)(∣x−xi∣,∣y−yi∣)
