# p13_5.py
def c2f(cel):
    fah = cel * 1.8 + 32
    return fah
    
def f2c(fah):
    cel = (fah - 32) / 1.8
    return cel

def test():
    print("测试，0摄氏度 = %.2f华氏度" % c2f(0))
    print("测试，0华氏度 = %.2f摄氏度" % f2c(0))

test()
