乌鸦喝水的练习。计算乌鸦要丢多少石头才能喝到水呢？如果假设乌鸦喝到的是毒药会怎样？如果石头是炸药怎样？适合java面向对象的初学者-Crow drinking practice. Calculate the number of crows to throw stones in order to drink water? If the assumption is that crow drink poison what would happ