weight=float(input("体重（kg）；"))height=float(input("身高（m）；"))bmi = (weight)/(height**2)print('您的BMI指数为%f'%bmi)if bmi<18.5:    print('过轻')elif bmi<25:    print('正常')elif bmi<28:    print('过重')elif 28<=bmi<32:    print('肥胖')else:    print('严重肥胖')input("单击退出；")